El embrión está creciendo

Cuando una mujer nota que no ha tenido su período y su prueba de embarazo es positiva, normalmente ya han pasado de dos a seis semanas desde el primer día de su última menstruación. La concepción ocurre 14 días antes del primer día del período menstrual esperado, pero la mayoría de las mujeres no saben que ha ocurrido. Cuando una mujer obtiene un resultado positivo en la prueba de embarazo, el embrión ya mide unos 5 milímetros. Parece diminuto, pero su columna vertebral ya se está formando, su corazón está organizando sus primeros latidos y los contornos embrionarios de los diversos órganos ya están allí.

La futura madre

Una mujer puede empezar a sentir la presencia de hormonas del embarazo en su cuerpo. Aunque la falta de menstruación suele ser el primer síntoma del embarazo, los cambios en los senos comienzan poco después. Los senos comienzan a hincharse e incluso pueden empezar a sentirse adoloridos debido a la estimulación provocada por las altas concentraciones de progesterona producidas por los ovarios. Los niveles sanguíneos de la hormona del embarazo, la gonadotropina coriónica humana (hCG), que se duplica en concentración cada 48 horas, pueden causar náuseas matutinas y vómitos. Las mujeres también pueden notar un aumento de la fatiga, la sed, la micción y la retención de líquidos. El sistema renal, que regula los líquidos, provoca un aumento de la retención de líquidos y del volumen sanguíneo hasta un 50 %. El ritmo cardíaco y la frecuencia respiratoria de una mujer embarazada se aceleran.

Información importante

Es importante que la futura madre llame para programar su primera visita prenatal con su obstetra, ginecólogo, comadrona o enfermera profesional en cuanto sepa que está embarazada. Durante esta primera visita, la madre recibirá toda la información necesaria para que su embarazo tenga un inicio saludable. En esta visita, el proveedor de atención médica revisará el historial médico de la madre y hará recomendaciones sobre los comportamientos de salud que deben cambiarse, como dejar de fumar o de beber alcohol. Probablemente se le recomendará que empiece a tomar vitaminas prenatales, se hablará de las vacunas recomendadas (por ejemplo, una vacuna contra la gripe), y proporcionará recomendaciones o diagnósticos terapéuticos para hacer que el embarazo sea lo más seguro posible tanto para la mujer como para el feto en desarrollo.

CONSEJOS:: Una vez que su prueba de embarazo sea positiva, llame a su centro de atención médica

El embrión ahora mide 5 mm de largo, pesa menos de 1 g y tiene forma de «C»: la cabeza en desarrollo es solo una protuberancia que mira hacia la punta de la cola. A los lados del embrión podemos ver los contornos diminutos de las futuras extremidades. El corazón es muy pequeño pero ya es capaz de bombear sangre a través de los vasos sanguíneos, aunque todavía no tiene un tamaño suficiente como para poder verlo u oírlo mediante ecografía. El líquido amniótico, que asegura un ambiente óptimo para el crecimiento embrionario, es proporcional al volumen del embrión que lo produce y filtra los líquidos, desde su sistema circulatorio hasta su piel primitiva.

La futura madre:

Una vez que la prueba de embarazo ha dado positivo, el sistema renal retiene agua para aumentar, gradualmente, el volumen de sangre de la futura madre. En el primer trimestre, una mujer tiene alrededor de un litro y medio más de volumen sanguíneo del que tenía antes de concebir. El flujo sanguíneo a los riñones ha aumentado tanto que produce alrededor de un litro más de orina que los dos litros producidos normalmente cuando no está embarazada. La necesidad de orinar se vuelve frecuente, lo cual debe tenerse en cuenta cuando se viaja o en lugares donde no siempre es fácil encontrar un inodoro.

Información importante:

A las cinco semanas del último período, una ecografía trasvaginal debería poder visualizar el saco gestacional, lleno de líquido amniótico, en la cavidad uterina. Esta prueba no es necesaria para todas las mujeres embarazadas, sin embargo, en el 1 % de los casos, el embarazo se produce fuera del útero, generalmente en las trompas de Falopio («embarazo tubárico» o «embarazo ectópico»). Con un diagnóstico oportuno, es posible identificar un embarazo fuera del útero, lo que requiere una intervención médica o quirúrgica inmediata. Las mujeres que han tenido infertilidad, cirugía previa del tracto reproductivo o infecciones pélvicas tienen mayor riesgo de sufrir un embarazo extrauterino. Una secuencia de diagnóstico completa, primero con pruebas de hCG y luego con ecografía, reduce la posibilidad de que se pase por alto este diagnóstico.

El embrión está creciendo muy rápido y ahora mide 7 mm de largo, desde la punta de la cabeza (el ápice del cráneo o la corona) hasta los huesos del coxis (trasero). La actividad cardíaca debe ser visible mediante una ecografía trasvaginal y la frecuencia cardíaca es superior a los 100 latidos por minuto. El corazón es pequeño y tiene que trabajar a una alta frecuencia para poder distribuir la sangre a un embrión pequeño pero que crece muy rápidamente. El embrión comienza a tomar forma humanoide y se pueden ver rastros de los contornos de las extremidades. La posibilidad de aborto espontáneo disminuye al 2 % una vez que la ecografía logra detectar los latidos del corazón; esto se considera evidencia de la vitalidad embrionaria.

The mother to be

La cantidad de sangre que circula en las arterias y venas aumenta en un 50 %. El sistema linfático de la mujer es rico y vital, su piel es particularmente brillante y luminosa y su cabello es más fuerte. Desde un cierto punto de vista, es como si ella hubiera recibido una recarga completa; por el contrario, muchas mujeres sienten una gran fatiga de forma espontánea. Estos cambios físicos pueden ir acompañados de cambios emocionales impredecibles. Algunas mujeres sienten una tremenda emoción y felicidad por la alegría de haberse quedado embarazadas y por las expectativas de ser madre. Por otro lado, ciertas emociones compiten con la conciencia de que la propia vida está a punto de cambiar. Muchas futuras madres se sienten atraídas por el futuro que les espera, pero también pueden sentir cierta ansiedad por las muchas incógnitas que esto conlleva. Algunas mujeres pueden no estar del todo contentas con su embarazo y pueden tener sentimientos de ansiedad, desesperación o ambivalencia. Aunque estas dudas son perfectamente normales, por lo general se acaban disipando. Hay un porcentaje significativo de mujeres que pueden desarrollar depresión durante el embarazo, especialmente si ya la han sufrido antes de quedarse embarazadas o si el embarazo ha sido inesperado.

CONSEJOS: Si le preocupa esto, consulte con su médico lo antes posible para obtener la atención adicional que necesita.

Información importante

El embarazo es una buena oportunidad para dejar de fumar y para evitar la exposición al humo de forma pasiva. El humo del tabaco reduce considerablemente la cantidad de oxígeno disponible para el embrión en desarrollo y puede provocar que el feto pese hasta 100 gramos menos al nacer que si la madre no hubiera fumado. Para un adulto, 100 gramos es una pequeña fracción del peso corporal. Sin embargo, durante el desarrollo prenatal, la grasa corporal es mínima; esos 100 gramos se pierden de tejidos como músculos, huesos y nervios. Las mujeres que no pueden dejar de fumar deben hablar con sus médicos acerca de los recursos disponibles para ayudarlas.

En la séptima semana de amenorrea es posible ver el saco gestacional con una ecografía trasvaginal. Es posible ver cómo el corazón del embrión bombea la sangre a todo el cuerpo. La actividad metabólica aumenta de un 10 a un 25 %, los latidos del corazón y la frecuencia respiratoria se aceleran y la musculatura uterina se fortalece y se estira. Esto puede contribuir a que la madre se sienta abrumada por la fatiga. No hay evidencia de que el sexo, el ejercicio o los viajes puedan causar problemas a las futuras madres que no posean ningún factor de riesgo conocido y cuyos médicos no les hayan indicado lo contrario.

CONSEJOS: pregúntele a su médico si hay actividades que se deberían evitar o limitar en su caso particular.

A las ocho semanas el embrión ha crecido hasta alcanzar un tamaño de 1,6 cm aproximadamente. De ahora en adelante abandonaremos el término embrión y usaremos feto para designarlo. Ahora es del tamaño de una judía, y la pequeña protuberancia trasera, la diminuta cola de las primeras semanas, ha desaparecido por completo. Comienzan a formarse las manos y los pies, y la ecografía nos muestra una forma con una fisonomía reconocible, los brazos y las piernas. Sus manos y pies, llenos de huesos incipientes, se ven con claridad, y se pueden contar los dedos de las manos y de los pies. Esta es una de las principales diferencias con respecto a las semanas embrionarias, en las que la morfología mostrada por la ecografía era la de una estructura alargada cuyo único signo de vitalidad consistía en la contractilidad rítmica del corazón. Si la ecografía se prolonga unos minutos, ahora será posible observar los primeros movimientos fetales.

En esta etapa del desarrollo, el feto ya ha sufrido numerosos desafíos de salud, y el riesgo de aborto espontáneo sigue disminuyendo por debajo del 2 % de la sexta semana, cuando se pudo comprobar por primera vez el ritmo cardíaco embrionario.

La futura madre:

Si la futura madre está sufriendo náuseas, tenemos malas noticias: el final todavía está lejos, ya que estas podrían continuar hasta la 12.ª semana en el 90 % de las mujeres, así que lo mejor será revisar la estrategia de alimentación y terapia para obtener algún alivio.

TIPS: consulte con su médico para que le dé sugerencias sobre alimentos o terapias que le ayuden a aliviar las náuseas

La cantidad de ADN introducido en el torrente sanguíneo de la madre desde la placenta es muy limitada y aún no es suficiente para poder analizar anomalías cromosómicas, pero ya es posible detectar el ADN del cromosoma Y para conocer el sexo del feto. Para las madres que pueden transmitir trastornos ligados al cromosoma X, como la hemofilia, esta información es importante porque todas las hijas serán portadoras del rasgo pero no se verán afectadas, mientras que la mitad de los hombres, en el caso de la hemofilia, correrán el riesgo de sufrir una deficiencia de coagulación y será necesario planificar más pruebas para ver si se ven afectados o no por dicho trastorno.

Su feto está creciendo

El feto mide ahora alrededor de 3 cm y pesa algo menos de 3 gramos. El cuerpo ahora está más erguido y la forma de la cabeza está más definida. La estructura básica de los principales órganos internos ya está bien delimitada.

La futura madre:

Los senos aumentan su volumen tan rápidamente que pueden provocar dolor. Algunas mujeres experimentan una extrema sensibilidad en los pezones, llegando incluso a negarse a usar sostén; la mayoría de las mujeres necesitarán un sostén más grande y que preste un mayor apoyo. Otra queja recurrente para casi todas las mujeres es la alteración de su ritmo de sueño y vigilia. Es como si sus relojes biológicos se hubieran alterado por el jet lag. Las cosas también cambian en el cerebro. La base del cuarto ventrículo del cerebro y el sistema receptor de olores y sabores cambian tanto que las mujeres pueden experimentar antojos o rechazo de ciertos alimentos; algunos olores de los que antes disfrutaban se vuelven insoportables. El malestar matutino y las náuseas pueden continuar. De vez en cuando, durante este tiempo, algunas mujeres pueden experimentar manchado o sangrado vaginal, lo que puede hacer saltar sus alarmas ante el temor de que el embarazo esté en riesgo. En la mayoría de los casos, esto es solo parte del mecanismo rutinario que elimina parte de la placenta y no indica ningún riesgo para el embrión.

CONSEJOS: si tiene alguna duda, póngase en contacto con su médico.

Información importante

Por lo general, la madre puede seguir ejerciendo todas las actividades habituales, incluyendo viajes, ejercicio o sexo. En una situación ideal, a estas alturas la madre ya habrá experimentado su primer control obstétrico:

• lo mejor es que se haga lo antes posible en cuanto la prueba de embarazo resulte positiva;
• un análisis de sangre para identificar el grupo sanguíneo de la futura madre y el factor Rh;
• un conteo sanguíneo completo (hemograma), pruebas de glucosa en la sangre y de química sanguínea (para verificar el funcionamiento adecuado del hígado y de los riñones) pruebas de anticuerpos específicos para toxoplasmosis, citomegalovirus, hepatitis B, C, VIH y sífilis, y una prueba de Coombs.

En general, la madre puede seguir haciendo casi todas las actividades físicas y deportivas que realiza normalmente. Esto se aplica a la mayoría de las mujeres durante todo el embarazo. Ahora hay suficientes pruebas científicas para disipar los temores de las mujeres: pueden correr, saltar, hacer footing o dar volteretas si lo desean, sin que ello afecte a su gestación. Del mismo modo, pueden seguir montando en bicicleta y, en general, pueden practicar casi todos los deportes, excepto el salto en paracaídas y el submarinismo con oxígeno, dos actividades que podrían afectar al paso del aire entre la placenta y la pared uterina, con el consiguiente riesgo de embolia. El esnórquel, normalmente, está permitido. Sin embargo, hay algunas mujeres cuyos embarazos están clasificados como de alto riesgo. En estos casos, el médico aconsejará a la madre qué actividades puede y cuáles no puede seguir haciendo.

La décima semana pasaba casi desapercibida, puesto que la madre y el médico estaban esperando el final del primer trimestre para medir la translucencia nucal y calcular el riesgo de anomalías cromosómicas, principalmente la trisomía 21 (síndrome de Down) y las trisomías 13 y 18. Ninguna de las otras trisomías, salvo raras excepciones, permiten que el feto llegue hasta la 12.ª semana. Hace unos años, esta capacidad diagnóstica parecía inalcanzable; en ocasiones anteriores había resultado imposible utilizarla clínicamente para el diagnóstico prenatal de trisomías. Ahora, en cambio, está disponible para las futuras madres. Estas pruebas se basan en la dosis de ADN liberado por las células placentarias (trofoblastos) a la circulación materna y permiten detectar un exceso de ADN debido a la presencia de dos cromosomas maternos y uno paterno. Este desequilibrio cromosómico se denomina trisomía; se debe a una disyunción (separación) fallida del par de cromosomas del óvulo materno. Todo lo que esta prueba requiere es una muestra de sangre materna, pero no se debe subestimar su impacto en el embarazo. La madre y su pareja deben recibir asesoramiento completo sobre la sensibilidad de las pruebas de trisomía u otras anomalías cromosómicas y sobre la posibilidad de resultados falsos positivos que requieran una amniocentesis posterior para confirmar o descartar la posibilidad de trisomía. Las parejas que no consideren aceptable tener un hijo con síndrome de Down deberían llevar a cabo este examen. Del mismo modo, las parejas que sí acepten dicha posibilidad pueden realizar la prueba igualmente. Habrá que tener en cuenta que, en el caso de un resultado positivo falso, no sería razonable proceder con la amniocentesis porque, aunque las probabilidades sean mínimas, existe el riesgo de aborto espontáneo u otras complicaciones derivadas de ella. Estos temas complejos se tienen que estudiar en detalle antes de proceder a tomar una muestra de sangre para este tipo de análisis.

CONSEJOS: si tiene alguna duda, póngase en contacto con su médico.

El primer trimestre está a punto de terminar. El riesgo de aborto es inferior al 1% porque únicamente las trisomías 13, 16, 18 y 21 permiten llegar hasta esta fase del embarazo (el desequilibrio cromosómico de las otras trisomías no permite que el feto sobreviva hasta esta semana). Las mujeres que han estado sufriendo náuseas ponen sus esperanzas en el final del primer trimestre, que es cuando nueve de cada diez mujeres dejan de padecer este molesto trastorno. Las náuseas durante el embarazo se deben principalmente al componente beta-glicoproteico de la hormona del embarazo (hCG). Los genes que regulan la producción de este componente de la hormona del embarazo están en un cromosoma diferente del que regula la producción del componente alfa de la misma hormona. En la semana 12 hay una fuerte caída en la síntesis del componente beta y las náuseas generalmente desaparecen. En caso contrario, a menudo es necesario tomar vitaminas (vitamina B6) o medicamentos capaces de inhibir la activación de la base del cuarto ventrículo del cerebro, que es la fuente de estímulos para las náuseas y el vómito. Este mecanismo tiene una función protectora, pero en este caso no tiene razón de ser y simplemente genera molestias que pueden durar, no solo hasta el primer trimestre, sino hasta la 21.ª semana. En algunos casos persiste incluso hasta el parto.

El feto está creciendo

El feto de 12 semanas ahora tiene una apariencia reconocible. Mide entre 5 y 6 cm de largo y pesa aproximadamente 15 gramos. Su rostro es reconocible: podemos ver los ojos, la boca y los labios. Sus manos y pies ya pueden articular movimientos, y el feto puede moverse en su líquido amniótico, jugar con su cordón umbilical o llevarse el dedo a la boca. A las 12 semanas también es posible estudiar su complemento cromosómico midiendo el grosor de la translucencia nucal, realizando pruebas bioquímicas o analizando la cantidad de ADN liberado por la placenta. En algunos casos se recomienda un análisis del tejido placentario (muestra de vellosidades coriónicas, o MVC), aunque el procedimiento tiene un riesgo de aborto espontáneo de un caso por cada 150 muestras.

La futura madre:

El fondo uterino es ahora lo suficientemente voluminoso como para aparecer como una pequeña hinchazón por encima del hueso púbico. La ropa que se usaba antes del embarazo comienza a quedar apretada alrededor de la cintura. Para la mayoría de las mujeres, las náuseas matutinas y las náuseas casi han desaparecido, pero podrían persistir en algunas mujeres. Los senos casi han duplicado su volumen y el cabello de la madre está, por lo general, más brillante y liso. Muchas de las mujeres que, previamente, habían experimentado cambios de humor frecuentes notarán que ahora son menos frecuentes y que son más positivas. Además, otras funciones fisiológicas podrían volver a ser más regulares. La necesidad de orinar puede que ya no sea tan frecuente: el útero está empezando a salir del estrecho embudo de la pelvis, tiene más espacio y ya no está presionando contra la vejiga. La vigilia matutina y el insomnio, frecuentes durante el primer trimestre, comienzan a disminuir. La fatiga abrumadora se reduce. La vida sexual de la pareja a menudo reanuda su ritmo natural ahora porque la futura madre ya no se ve obstaculizada por las dificultades de los cambios fisiológicos iniciales. Los senos ya no le duelen tanto, y su útero tiene más espacio para que el pene se deslice cuando se introduce en la cavidad vaginal.

Información importante:

Para controlar su bienestar y el del feto en la semana 12, una futura madre debe hacer lo siguiente:

• exámenes prenatales rutinarios con la frecuencia que su médico le recomiende análisis para comprobar la concentración de hemoglobina y plaquetas sanguíneas;
• un análisis de orina para asegurarse de que todo esté en la norma;
• una prueba de toxoplasmosis si la primera prueba no mostró anticuerpos, para ver si el resultado sigue siendo negativo;
• una prueba de citomegalovirus para asegurarse de que a) una futura madre que dio negativo en la primera prueba siga mostrando el mismo resultado, o b) una futura madre que dio positivo a los anticuerpos no haya sufrido una reactivación del virus;
• una muestra bioquímica, si así lo solicita, para estudiar el complemento cromosómico del bebé;
• muestra de vellosidades coriónicas (solo si se considera necesario después del resultado de los análisis de sangre de la madre).

El feto está creciendo

A las trece semanas el feto tiene apariencia humana, mide 7 cm de largo y pesa alrededor de 23 gramos, y sus movimientos se pueden ver en la ecografía. Las dimensiones del útero son tales que se siente fácilmente como una protuberancia redondeada sobre la sínfisis púbica.

La futura madre:

En esta etapa, la futura madre experimenta un cambio repentino en su percepción del embarazo porque la incertidumbre emocional y el entusiasmo que acompañan al primer trimestre dan paso a la plena realización de que, en unos pocos meses, se convertirá en madre. El riesgo de aborto espontáneo se reduce ahora a un caso de cada 500, y así permanecerá hasta la 37.ª semana. Muchas mujeres en esta etapa sienten la necesidad de hacer un balance de la situación con su médico, sobre todo con respecto a la dieta y el cuidado del cuerpo para los próximos meses. Se debe alentar a las mujeres embarazadas a que sigan su apetito y acepten normas de imagen corporal diferentes de las que tenían antes del embarazo. Los senos, por ejemplo, están siendo estimulados por la alta concentración de progesterona y están llenos e hinchados. Para las mujeres con senos pequeños, este hecho podrí resultar algo positivo, pero puede ser menos placentero para aquellas con senos más grandes; el exceso de peso puede resultar molesto. Todas las futuras madres deberían usar sostenes de apoyo que sujeten firmemente los senos contra la superficie del pecho para ahorrar esfuerzo e incluso evitar daños a los músculos pectorales provocados por el aumento del volumen. Los sostenes más adecuados son los deportivos, que tienen las correas cruzadas por detrás de la espalda para asegurar el máximo apoyo, una mayor comodidad y una mayor adherencia de los senos contra el pecho.

Información importante:

Se recomienda realizar una prueba de hemoglobina en sangre materna y un análisis de orina a todas las pacientes. Las mujeres que no tengan anticuerpos contra la toxoplasmosis y que cumplan con las recomendaciones para minimizar el riesgo de contagio deberán realizar pruebas de detección de anticuerpos para asegurarse de que no han comido nada contaminado por este protozoo. Dada la evidencia científica de que la inflamación bacteriana puede complicar el curso del embarazo, muchos especialistas en obstetricia prefieren comprobar, junto con estas pruebas, que el índice de actividad inflamatoria (proteína C reactiva, o PCR) esté dentro de los valores normales.

At fourteenth week of pregnancy, the waistline (circumference measured above the iliac spines) starts to grow almost visibly. When skirts and trousers start feeling tight, a simple remedy is to let them out with strips of elastic fabric in the stitchings, which are easy and economical to remove after childbirth to restore the original size of the garment.  Many women elect to wear larger size clothes or those specifically designed for maternity wear.   Many women complain of decreased intestinal transit and constipation, which may also be persistent and require dietary changes. The intestinal movement whereby food travels through the digestive tract (stomach, duodenum, small and large intestines) is called peristalsis. It’s a contractile wave that starts from the stomach and reaches the large intestine. It’s easy to see the gastrocolic reflex in infants. When a child eats, it almost immediately discharges food that’s already digested in the large intestine. This peristaltic wave is assisted by the cells of the smooth musculature of the intestinal wall, which are arranged obliquely to the intestinal axis and, on contracting, squeeze digested material along its path from mouth to rectum. When the rectum feels a sufficient quantity of feces, it triggers a local contracture that causes fecal material to be expelled. Progesterone, whose high concentration in the blood characterizes the entire course of pregnancy, is responsible for this de-synchronization of the smooth musculature activity. The same effect can be observed in the motility of the ureters, which are the tubular ducts enabling the kidneys to send urine to the bladder. Even the bronchi in the lungs feel the effect of progesterone: they become less tense and reactive and in some asthmatic patients this indirect effect of pregnancy is a benefit in terms of lessening their respiratory problems. For constipation, it’s useful to eat foods with a higher fiber content, such as whole meal biscuits, or food with a high sugar content, like fresh or dried figs, which draw a large amount of water from the intestinal walls. The aim of both these dietary measures is the same: to increase the fecal mass till it mechanically stimulates the intestinal walls to contract more effectively.  Many pregnant women may need to be advised to drink more water as well.

Fifteenth week of pregnancy: amniotic fluid contains exfoliated cells from the skin and mucosa of the fetus that can be cultivated in a laboratory to provide information on the fetus’s chromosomal composition. Ultrasound-guided sampling of amniotic fluid for pre-natal diagnosis began in 1966. Amniocentesis removes amniotic fluid with a needle similar to that used for taking peripheral venous blood, though thinner and obviously longer. Amniocentesis always requires an ultrasound guide to identify the most favorable zone to collect a sufficient amount of amniotic fluid without risking lesions to the fetus. The procedure only takes a few minutes. The woman’s abdomen is cleansed with antiseptic substances and the ultrasound probe identifies the precise point in which to insert the needle in the maternal wall to comfortably reach the amniotic sac. Around 15 ml of amniotic fluid (around 10% of the total volume) is usually taken. The sample volume varies with the stage of pregnancy but we avoid taking less than 10 ml because this would complicate and prolong the amniocyte culture procedure. The fetal cells are then  placed in culture to start their replication process. When the cells are in the replicative phase in which DNA spirals in the form of chromosomes, (metaphase), cells may be broken and chromosomes recovered, photographed and examined by a human genetics specialist. This procedure enables us to identify the chromosomal number and morphology and thus to identify whether the fetus is euploid (has a normal male or female chromosome make-up) or whether it has chromosomal abnormalities in number or structure. Amniocentesis has a miscarriage risk of one in every 200 samplings, even if carried out by an expert operator. Women who undergo amniocentesis for clinical reasons or anxiety about the normality of the fetal chromosome make-up should discuss all the aspects of this procedure with their doctor and human geneticist before proceeding with it.

Sixteenth week of pregnancy: the fetus is growing

Safe in its amniotic cavity and now in sixteenth week of pregnancy, the fetus is approximately 13 cm long (5 inches) and weighs 130 g (almost 5 ounces). It moves in an increasingly coordinated way now: for example, it will do rhythmical movements of flexion and extension, like a cat stretching its limbs. It touches its face, as if trying to understand what it looks like. It often sucks a finger or grips its cord as if it were an toy and not merely its source of oxygen and nutriment. The vague android look of the 1st trimester has given way to that of a boy or girl in miniature, with clearly visible eyebrows and more or less thick hair similar to the hair it will have at birth.

The mother to be: At this stage, the woman starts to feel fetal movements. The sensation of a new life growing inside her is no longer a matter of medical ultrasound tests, but an everyday reality. Her belly is growing, but is not yet an impediment; her breasts are full but are no longer painful; her skin and hair are probably vibrant and healthy looking. All these positive effects are the result of high blood hormone levels and of intense peripheral circulation feeding her entire body with abundant oxygen and nutrient substances. Important to know

At 16 weeks, with a pregnancy progressing regularly, your healthcare provider may recommend a few tests are needed to monitor the wellbeing of the mother and baby:

• a toxoplasmosis antibody test to confirm that they are still negative (if they were) and thus be sure that the mother-to-be hasn’t had contact with this parasite;
• an anatomy scan: the latest systems make it possible, even at 16 weeks, to examine the fetus with high precision so that most abnormalities may be excluded with high diagnostic precision. The fetus is monitored segment by segment. Ultrasound is so precise now that it’s possible to check, for example, the regularity of the esophagus or the conformation of the external genitals and also exclude minor abnormalities like harelip;
• 16th week amniocentesis for women at high risk or not sufficiently convinced by nuchal translucency ultrasound or the results of biochemical tests (B-test) or measurements of fetal DNA in the blood. Given the miscarriage risk with  amniocentesis, this is often a difficult decision.

From the seventeenth week of pregnancy, women may ask for a morphological examination of the fetus using 2-dimensional (2D) or 3-dimensional (3D) ultrasound. Most examinations are carried out in the former mode but most specialists also make selective 3-dimensional examinations for specific anatomical regions, such as the face. It’s very important for these examinations to be carried out by fully experienced diagnostic specialists using state-of-the-art instruments of high diagnostic power. Sixteen weeks and a few days is considered the minimum amenorrhea period in which to conduct this examination. Women who have already undergone non-invasive or invasive testing (Non Invasive Prenatal Testing – NIPT; Chorionic Villus Sampling – CVS, or amniocentesis) must in any case proceed with this examination if they want to rule out fetal malformation not tied to chromosomal abnormalities. Most medical societies formulate fetal morphology analysis and recording standards in ways that reduce diagnostic error to a minimum. Women must be informed that this morphological examination is not able to identify all the possible fetal malformations, but it can provide a reassuring picture in which all major malformations and most of the minor ones can be ruled out with a high degree of reliability. For example, at the 17th week a prenatal ultrasound operator is not able to examine with full diagnostic reliability the morphology and heart dynamic of a fetus. A second ultrasound examination would be needed at the 20th week or later to be able to study the fetal heart in full detail. In select cases where a malformation is suspected, the ultrasound operator will advise whether further procedures and consulting are necessary to obtain a more accurate diagnosis.

Eighteenth week of pregnancy: the fetus is growing

At eighteenth week of pregnancy the fetus weighs 190 grams and is 14 centimeters long. It’s moving a lot, especially at night when the mother’s circulation system is centralized and the placenta is receiving more blood.

The mother to be:

If the woman is in her first pregnancy, she might not yet be able to perceive the fetus’s movements because its mechanical energy and the thickness of the uterine walls do not sufficiently stimulate the abdominal wall. In women who have already had children (multiparas), the uterine wall is thinner and movements can already be clearly felt. A multipara at 18 weeks who’s expecting twins, for example, can generally distinguish the movements of one or the other. Perceiving fetal movements is usually an emotional event: what was once trusted to the imagination—or to ultrasound imaging—now becomes a visceral reality. By this week, a woman who underwent fetal chromosome already has all the results showing normality; if the morphological picture previously examined didn’t detect any abnormality, she can feel the relief that helps her tolerate all the inconveniences that characterize pregnancy.

Important to know:

One very common disorder is the alteration of the sleep-wake rhythm, which characteristically produces an uncontrollable sleepiness in the late afternoon and early wakening before dawn, a bit like jet. If a woman is in her first pregnancy, and has a flexible work schedule, she can try taking naps during the day to make up for disturbed and unrestorative sleep; this is almost impossible for women with other children and/or those with a demanding or inflexible work schedule. Unfortunately there are no pharmacological remedies for these altered sleep patterns and the mother-to-be has to learn to live with it because the substances that act on the “sleep center” must be liposoluble to penetrate the cerebral matter; all such drugs can easily cross the placental barrier and the fetal brain. Such a pharmacological influx would reduce fetal reactivity and could interfere negatively with the functional maturing of the fetal brain, with negative consequences on a cognitive level. This is why psychoactive drugs are not to be used during pregnancy, unless strictly necessary to control a  significant psychological disturbance. The reasons for this sleep disruption are not known.  We can only form functional hypotheses, one of which is that it it an evolutionary adaptation which prepares a woman to stay awake at night to protect and feed her baby, given that thousands of years ago the risks posed by nocturnal predators required constant vigilance. The pattern of this sleep disorder in pregnancy has been well studied regarding both the rapid eye movement (REM) phase and unmotivated awakening after going to sleep. There are a few useful tips for women here: a comfortable bed; sleeping alone occasionally to avoid disturbing her partner when she’s awake at night or not be disturbed by her partner in the few hours of sleep she does get; eating very small evening meals so that everything can be digested before going to bed; emptying the bladder immediately before bed; and ensuring a comfortable temperature and humidity control in the bedroom. While these tips may help, they won’t actually solve the problem.

In the nineteenth week of pregnancy, the uterus is now voluminous and occupies all of the pelvis, which makes it harder work for venous blood returning from the legs to re-enter the circulation of the portal venous system (portal vein). The blood that supplies the legs returns to the central circulation by way of the two iliac veins that unite in front of the most protruding part of the spine (promontory) and converge in the portal vein. The posterior wall of the uterus rests on the promontory and this is why the venous flow is partially disturbed. Nature adapts and has remedied this particular mechanical conflict by shifting the portal vein laterally to the right of the spine and tilting the uterus towards the right (dextro-rotation of the uterus). There is more room on the right of the pelvis in fact, because the terminal part of the large intestine is blind (hence the term “blind gut”), while to the left the descending colon joins the sigmoid colon to reach the rectum and thus occupy a confined anatomical space between the lateral ilia, the spine posteriorly and the pubic symphysis anteriorly. Most women notice that their legs are more swollen at the end of the day and that this swelling generally disappears during night time rest. The large quantity of blood that a mother-to-be has produced since the first weeks of pregnancy to guarantee efficient supply to the placenta and which is accommodated in the venous system now becomes perceptible: the veins are swollen and those in the legs are affected by hydrostatic pressure. The hemorrhoidal venous plexus often starts to make itself felt, with protrusion of the hemorrhoidal veins and sometimes slight bleeding from congestion (accumulation) of blood in the circumflex veins of the venous system surrounding the final tract of the intestine, the anus. To decrease venous dilation in the legs, it’s advisable for mothers-to-be to wear 70 denier elastic stockings when they have to spend hours on their feet or travel for more than two hours. These stockings are easy to find and are typically worn by shop assistants and flight attendants to prevent hydrostatic pressure from causing seepage of fluid through the venous walls, leading to uncomfortable swelling that requires several hours of horizontal rest (eg. night time sleep) to be reabsorbed. To reduce congestion of the hemorrhoidal plexus, the main recommendation is to keep the rectum free from fecal accumulation, which makes venous return more difficult. If advised by a doctor, it’s possible to use creams that cause the venous walls to contract or anal dilators that reduce the tone of the anal sphincter (the circular muscle around the anal aperture), which when contracted prevents the return of venous blood from the hemorrhoidal plexus. Dietary changes may also be advised.

Twentieth week of pregnancy: the fetus is growing

20 In the twentieth week of pregnancy the fetus is 16 cm long (approximately 6 inches) and weighs 340 g (12 ounces). Its growth rate, very fast up to now, slows down to allow the lungs, gastrointestinal tract and immune system to mature. It can hear and may react to loud noises by jumping or kicking.

The mother to be:

The belly starts hindering certain movements. Towards the 28th week it may be difficult to pick up something from the floor. At night, she may  have to get up to urinate because of the huge quantity of urine that pregnancy makes her produce. She may also suffer from leg cramps at night due to excessive loss of minerals through urine. About a third of women may start to feel burning sensations in the stomach at this stage. Pressure from the now voluminous uterus causes a reflux of a small amount of stomach acid  into the esophagus, causing discomfort. At this point the legs start to feel heavy because normal venous blood return is to a certain extent hindered at the pelvic level by the considerable size of the uterus.

Important to know:

It’s always best to take the healthcare provider’s advice. It is important to choose this person with great care; this should be someone the mother to be will trust. This is particularly important regarding nutritional supplements or any over-the-counter medications in pregnancy. The healthcare provider can advise her whether they are necessary or not and whether their potential benefits outweigh their risks.

Twenty-first week of pregnancy

From the 21st week onwards the uterus tends to shift to the right side of the spine and turn a little on its own axis. This position lowers the efficiency of urine flow from the kidney to the bladder via the ureter. Regular flow is vitally important: stagnant urine is an ideal  growth medium for  bacteria. Excessive bacterial growth in the urinary tract may cause urinary tract infections (UTI or pyelocystitis) — infection of kidneys, ureter or  bladder – in 3% of mothers-to-be. Pyelocystitis increases the risk of bacteremia (spread germs throughout the body via the bloodstream) and must immediately be treated with antibiotics to prevent pre-term labor or miscarriages due to micro-organisms released into the mother’s circulation. The choice of antibiotic depends on the bacteria identified in the urine and its sensitivity to the various antibacterial molecules; these are generally innocuous for the baby. Pain from pyelocystitis may be so acute that it requires one or two days in the hospital.

Twenty-second week of pregnancy: the fetus is growing

At the twenty-second week of pregnancy, the uterine fundus is around 3 cm (1.2 inches) over the transverse umbilical line, the abdominal section passing through the navel. The state of pregnancy is clearly visible. Complexion and hair are lustrous. The fetus is 28 centimeters long (11 inches) and weighs around 430 grams (15 ounces). From now on the fetus will grow at around 70 – 80 grams ( aprox. 2.5-2.9 ounces) a week, in huge steps of nearly 10 grams a day (0.3 ounce) , or 2% of its body weight. In a 70 kg adult ( 154 pounds) this would mean an increase of nearly 1.5 kg a day ( 3.3 pounds) , which would require a diet of at least 16,000 calories a day.

The mother to be:

At the twenty-secondo week of pregnancy dietary issues start to become more important for the mother-to-be. Medical societies make numerous recommendations for the optimal diet, based on a preponderance of carbohydrates, a fair quantity of protein and limited intake of fatty foods. The food pyramid has been around for nearly 50 years and there are differing opinions on its suitability and positive effect on the health of those who follow it. Alternatively, pregnancy can also be used to reflect on certain scientific findings that have emerged in recent years. The first is a preference for fresh as opposed to preserved foods. This may involve extra organizational effort but it gets the nutritional benefit out of food. The simplest example is with most fruits and vegetables, which inevitably lose some of their vitamin and mineral content, when cooked.  Tomatoes are an exception:  cooking increases the availability of lycopene.  Personally preparing fresh food may facilitate a more thoughtful approach to one’s diet, enhanced enjoyment of taste and lower consumption. Eating a diet high in prepacked food rarely meets users’ requirements because it’s geared to business considerations. In an industrialized world where food is often accessible, only a cultural attitude to what we eat can help us achieve a varied diet that enables us to indulge in favorable nutritional characteristics and limit unfavorable ones. A re-educational process in pregnancy may enable the mother later on to teach her child a sensible approach to food. We must be cognizant of the fact that there are still an unacceptable number of mothers-to-be who live in food-insecure situations which can present risks for her, her unborn child, and her child once it is born.

Twenty-third week of pregnancy: the mother’s weight has risen by around 10%, a third of which is from fluids in circulation and in tissues to optimize placental function, and the rest being fatty tissue deposits to facilitate alimentary autonomy after birth. These fat deposits also have an important function in creating a hormone storage system to support endocrine homeostasis throughout pregnancy. The fetus, on the other hand, has grown to over 500 times from the less than 1 g (0.03 ounce) it weighed at eight weeks gestation. If the mother had grown at the same rate, she would weigh 30 tons, like a whale! This comparison serves to illustrate how, in the reproductive biological model, the fetus is prioritized by the maternal system that provides it with oxygenation and nutrients for its growth. To consider the evolutionary bais for this, consider that the human reproductive system goes back over 250,000 years to a period when a woman after birth had to stay with her baby constantly to guarantee it warmth and protection. When nomad populations were constantly moving in search of food, women with newborns could not fully participate in gathering food or hunting. Having extra body fat reserves thus gave a new mother a time of alimentary autonomy. Given a weight gain of 10 to 15 kilos (22-33 pounds), providing some 90,000 to 135,000 calories, a nursing mother could potentially survive for  three months without much additional food. In industrialized countries, food sources are generally relatively easily accessed but the atavistic mechanism of weight gain in pregnancy has remained intact. During pregnancy, nature stimulates the woman’s appetite to be able to store calories to transform into adipose deposit. Women today often suffer from this weight gain excessively and many try to control their desire for food to contrast this mechanism. In most cases this should be discouraged to avoid incongruous diets depriving the fetus of nutritional substrates useful to its growth. There is another reason for encouraging women to follow their appetites: body fat accumulated in pregnancy provides a storage system for pregnancy hormones and enables a mother to more gradually face the post-partum period, when expulsion of the placenta causes hormone levels to drop to a fraction of what they were in the nine months of pregnancy. Mothers should be encouraged to keep up a balanced and healthy diet and accept a different idea of feminine beauty. The pregnancy weight gain, if the product of a sensible diet, will gradually disappear within six months of giving birth, spontaneously and without following any particular restrictive diet, especially if the mother is breast feeding. The constant appetite that characterizes the whole of pregnancy disappears, while efforts to look after the baby burn up sufficient calories to eliminate those stored during pregnancy.  While weight gain is the most common concern of pregnant women, we must be cognizant of the fact that there are still women with food insecurity both before and during pregnancy in whom gaining sufficient nutrition is a challenge.  There are also women with eating disorders and body dysmorphia which may impede optimal weight gain in pregnancy.

Twenty-fourth week of pregnancy: your fetus is growing

The fetus now weighs 630 g (22 ounces) and is 30 cm (12 inches) long. Surrounded by amniotic fluid it can move freely and is generally active. All the organs should be working except the lungs: it will take another few weeks before the alveoli and sacs that provide oxygen and carbon dioxide exchange are fully formed.

In the twenty-fifth week of pregnancy, the uterus is not an inert muscular container that gradually stretches to accommodate the growth of the placenta, amniotic fluid and fetus. The uterus periodically contracts throughout pregnancy and this contractile activity can already be recorded in the first weeks after conception. To understand the characteristics of this mechanism we must understand the characteristics of uterine muscular activity, which is based on smooth muscle fibers that are not controlled voluntarily (involuntary muscular activity) and communicate their contraction without needing nerve fibers to propagate the contractile stimulus, as happens for example in the heart, where a nerve bundle carries the stimulus from the atria to the ventricles. The uterus has a syncytial (syn= together; cytium = cell) muscular contracture mechanism in which, as the term suggests, the contractile stimulus is passed from cell to cell without nerves. The frequency and characteristics of uterine muscular activity in pregnancy were studied by an English physician, John Braxton Hicks, and his scientific work was so innovative that his name has been used ever since to define this phenomenon (Braxton Hicks contractions). This type of contractile activity (which could be more properly defined as contractures rather than contractions) generates non-painful hardening of parts of the uterine wall. Alarmed mothers-to-be often consult their doctors fearing that this may lead to a miscarriage or premature birth but they should be reassured; the absence of pain means that the contractions are localized (only affecting a limited area of the uterus). This localized activation of the muscles does not reduce blood flow to the muscular cells, so it doesn’t cause pain, unlike the contractions in labor that affect the entire uterine musculature. When labor starts, a zone of the uterine fundus acts as a pacemaker periodically sending out the contractile signal that spreads throughout the uterine musculature. Dr. Braxton Hicks established with electrophysiological experiments that there is contractile uterine activity throughout pregnancy. It’s only towards the 25th week, however, that women often notice them and may be alarmed. Prior to week 25 these contractions are rarely perceived, while nearly all women notice them in this phase of pregnancy.

Twenty-sixth week of pregnancy: the fetus is growing At twenty-sixth week of pregnancy the fetus weighs 750 – 800 grams (26-28 ounces)  and is approximately 35 centimeters long (14 inches). His or her prenatal development has produced a little human being that in the case of premature birth, or in clinical situations of which would require premature delivery, would have a 90% probability of survival. The neurological system is able to open the eyes; the fetus can see if the mother is in light and can react to sound stimuli transmitted through the abdominal wall and amniotic fluid. Fetal movements are clearly perceived by the mother, who can tell if it’s moving its arms or legs or if it performs sudden and repeated flexions and extensions of the whole body. In adults, this succession of rapid extensions of the trunk occur exclusively in the case of hiccoughs, due to the rhythmical contractions of the diaphragm when the gastroesophageal tract becomes irritated. This explains why the mother may think her baby is hiccoughing, when in fact baby is using this movement to exercise its back muscles. The fetus may also be enjoying the pleasing sensation of the brain moving inside its cranium.  In infants, delight in the movement of the brain in its cerebrospinal fluid can be seen in their love of swings and especially the moment the downward phase starts or when the pendulum motion ends with a thrilling cerebral shudder. As kids we never wanted to leave the swings (don’t stop!) and always wanted to go higher (push harder!). And as adults we have to grant these requests, with misgivings maybe, but the attraction of some movements are as strong as ever. The mother to be: Towards the 26th week many women complain of muscular cramps in the legs at night. The surface area of the mother’s body has increased nearly 50% and insensible perspiration, together with abundant production of urine, often causes hydro-electrolytic imbalances. During sleep, pregnant women don’t drink and they produce much more urine than during the day because the horizontal rest position at night favors reabsorption of liquids which, re-circulating, are drained by the renal function. Urine always contains sodium and potassium but when their hematic and intracellular concentrations drop low enough, muscle tone will be affected and the consequent contractions may be intense enough to decrease arterial blood flow (cramp). To combat this bothersome phenomenon women should know that flexion of the legs reduces tension in the gastrocnemius muscles (in the back of the legs) and therefore they should be encouraged not to sleep with legs stretched out and to drink a liter or more of a hydrosaline liquid like the ones used by athletes. A simple home recipe for this is to squeeze a citrus fruit (rich in potassium), dilute the juice in a liter of water and add a teaspoon of ordinary table salt, which contains chlorine and sodium (sodium chloride in fact). If this basic product is too simple for one’s taste, it can be improved with sugar or flavored syrups.

At twenty-seventh week of pregnancy most fetuses weigh 800 grams (28 ounces) and are nearly 40 centimeters long (approximately 16 inches). This is a crucial phase in pregnancy because the placenta is preparing to take a fetus of around 1,000 grams (35 ounces) to its definitive weight at birth of around three kilos. This is worth thinking about, because in seven months the fetus has only completed a third of its growth, and then grows threefold in just three months. Simply put, this means that up to 27 weeks a fetus grows at an average rate of 37 grams (1.3 ounces) every seven days, and then grows three times faster, at 170-200 grams a week (6-7 ounces). This requires a perfectly functional placenta. It is at this point that placentas may show signs of insufficiency in terms of either their structure or the way they interact with the uterine wall. One of the numerous hypotheses seeking to explain the phenomenon of pre-eclampsia (increase in arterial pressure in the 3rd trimester of pregnancy accompanied by kidney damage and proteinuria) sees the increase in pressure as an attempt to correct placental insufficiency by increasing the pressure of its blood perfusion. Whatever the origin of this arterial hypertension, the sooner the problem is identified the better, so that intensive monitoring and pharmacological treatment may be started. Blood pressure should be checked at every obstetrical examination. In this phase of pregnancy, women whose diastolic blood pressure is 80 mm Hg or higher must be informed of the need for daily blood pressure monitoring, because the onset of pre-eclampsia may be sudden. The usual monthly obstetric check up is not frequent enough to ensure prompt pharmacological action to control an increase in pressure. The mother-to-be must be constantly monitored and hospitalization is sometimes necessary to keep maternal and fetal wellbeing under constant control. In women with pre-eclampsia, fetal growth is delayed and may cease altogether, with the risk of perinatal death. It thus becomes crucial to choose the week in which to deliver the fetus, with the risk of premature birth balancing the dangers of staying in the uterus. The most basic therapy for pre-eclampsia is birth, because the removal of the placental tissue interrupts the hypertensive stimulus in most cases almost immediately and in a third of women in the months following birth. With frequent obstetric check-ups in centers specializing in pre-eclampsia and which have intensive prenatal therapy units capable of giving premature babies all the necessary assistance, there can be a successful outcome for mother and baby. A simple, periodical pressure test is the best guarantee of timely identification of women who risk developing pre-eclampsia and of effective intervention.

Why Twenty-eighth week of pregnancy is crucial

Twenty-eighth week of pregnancy: it is important to perform Coomb test for women with Rh negative blood group where the father of the child is Rh positive, to exclude the possibility that they haven’t been immunized; at this stage such women must take anti-D immunoglobulin to prevent microscopic placental hemorrhages causing immunity towards the Rh factor.

Your fetus is growing

The fetus measures nearly 40 cm (9.8 inches) now and weighs around 1 kilogram (35 ounces). At this stage the baby is  often capable of interacting with its mother. Some are livelier than others and they all have their own characteristics in terms of activity and rest phases and varying degrees of adaptability to mother’s life and habits. Some seem like rough customers who love to play football with mom’s gall bladder to make her change position, while others are more accommodating. At 28 weeks, the placenta goes into overdrive. Thanks to the increase in the placenta’s transplacental nutrient function, the baby starts to gain around 150 g a week (5 ounces). Such acceleration is remarkable: having taken 28 weeks to reach 1 kg (35 ounces), it will now need only 12 more weeks to reach the average birth weight of 3.5 kg (7.7 pounds), a big change demonstrating the fundamental role of the placenta during this trimester. When it can’t effectively perform its function in fact, the baby grows more slowly and the mother’s body may  suffer, with maybe an increased blood pressure and possible development of pre-eclampsia. This condition affects around 5% of mothers-to-be.  While it is treatable in most cases and does not prevent the baby from reaching full maturity, it is responsible for 15% of pre-term births in the US .

The mother to be:

Expecting mothers may be bothered by nighttime leg cramps  due to excessive loss of minerals through urine. There is a natural remedy to this: every now and again drink fresh citrus fruit juice, rich in potassium, with the addition of a teaspoon of table salt.  Some women also swear by drinking pickle juice as a home remedy.  Important to know: 

At 28 weeks, the steps to take for peace of mind and the best pregnancy outome in the final trimester, leading up to delivery, are: – It is important  to attend the regularly scheduled prenatal visits.  The healthcare provider may suggest  an ultrasound to check fetal growth and regular blood flow via the uterine arteries and umbilical cord. Check-ups and ultrasound together can detect any slowing down in fetal growth (which will now require specific care) or placental pathologies. Most women now start wanting to talk about delivery techniques: the big day is drawing close and the mother-to-be quite rightly wants to be psychologically and logistically prepared. – mother’s blood test to check that blood sugar  levels are normal and hemoglobin concentration is not unduly diminished; – a check up of the urinary function to make sure it has been maintained; – a urine test to check there are no traces of protein or glucose and a urine culture to exclude any asymptomatic urinary infection; – toxoplasma antibody test.

Twenty-ninth week of pregnancy: the fetus is growing

At twenty-ninth week of pregnancy the fetus is beginning to weigh considerably over 1 kg (35 ounces) , and is growing fast at nearly 200 g a week (7 ounces). This growth rate varies with the genetic potential of the fetus and the placental function, from 100 g to over 200 g a week, and will determine weight at birth. Thanks to a mechanism still not wholly understood, the fetus starts to take on the dimensions of the canal between the pelvis bones, through which it will have to pass to be born, and regulates its growth in order to be able to achieve this smoothly.

The mother to be:

By now the belly seems really big! It may be challenging to find a comfortable position; while standing, she has to significantly arch her back to avoid tipping forward. Pregnancy hormones like relaxin impact the articular system; this hormone increases the mobility of the pelvic bones and may make her feel more unsteady on her feet. Sitting down and getting up become an effort and resting at night, until now disturbed only by insomnia, is even more challenging due to both the bulk of her belly and the fetus’s vigorous kicking. Legs tend to feel heavy, especially at the end of the day. In this and the following weeks, in addition to the annoyance of constipation that characterizes most pregnancies, there is a possibility of painful hemorrhoids. This will mean closer attention to diet and trying to keep feces soft to avoid aggravating hemorrhoidal congestion through excessive strain to evacuate. If hemorrhoids become a misery, ice is an extremely useful decongestant and mini-ice pops in particular, if inserted up to or even past the sphincter, may produce a “miraculous” effect, strange as it may seem. Some women, on the other hand, find rinsing with tepid water relieving. There are also vegetal extracts that tone up the vein walls. This reduces congestion and the risk of blood stasis forming tiny clots inside the hemorrhoids.

Important to know:

Resting with the legs elevated—ideally, lying down– is very important. So at work, if possible, she has to rest her legs on some support, which could, compatibly with her occupation, be another chair. At home, the couch is OK. If she has swelling in her legs, her healthcare provider may recommend support socks and extra rest.

Thirtieth week of pregnancy: the fetus is growing

From the thirtieth week of pregnancy, interaction with the outside world also becomes more significant. Mothers may notice that the fetus reacts differently to certain foods and that certain pieces of music or movements stimulate more or less activity. In this period, the fetus’s muscular force is already considerable: assertive movements manifest its reaction to mom’s behavior.

The mother to be:

Acid reflux from the stomach to the esophagus is a common problem and often highly unpleasant. The common antacids, which are not absorbed, should be kept close at hand.

TIPS:  it’s advisable to talk with your doctor about medicines that reduce gastric acid secretion which causes heart burn. These medicines are generally considered safe to use in pregnancy. 

Important to know:

If the pregnancy is progressing uneventfully, no more ultrasounds are necessary at this point, so the things to do are: – routine obstetric appointments – routine blood tests: complete blood count, blood sugar level, serological testing for toxoplasma and cytomegalovirus antibodies in negative women – urine test to exclude the presence of sugar, protein and bacteria – the doctor may recommend additional tests if she has excessive swelling or any other unusual symptoms – some parents may consider whether, at birth, to take stem cells from the umbilical cord and cryo-conserve them for possible future use. Cost and family history are significant factors in this decision.

Thirty-first week of pregnancy: the fetus is growing

In this thirty-first week of pregnancy the fetus is now a little adult and weighs over 1 Kg (35 ounces). All its enzymatic systems are mature enough to ensure survival in the case of premature birth, even without intensive care. The placenta, which enabled a few embryonal cells to grow to 1 kg in seven months (28 weeks), has now managed to double the weight of the fetus in just four weeks. It’s in this period in fact that the placenta changes its fetal nutrition process to enable rapid body growth. The mother notices the fetus’s vigorous reactions when she adopts a position it finds uncomfortable, and even the obstetrician can easily perceive the fetus’s movements: the baby kicks and punches in fact when the ultrasound probe disturbs its peaceful prenatal existence.

The mother to be:

Expecting mothers may be bothered by nighttime leg cramps due to excessive loss of minerals through urine. There is a natural remedy to this: every now and again drink fresh citrus fruit juice, rich in potassium, with the addition of a teaspoon of table salt. Some women also swear by drinking pickle juice as a home remedy.

Important to know:

When it’s night for the mother, it’s day for the fetus. The baby perceives daylight and nighttime darkness but lives in a sort of jet-lag caused by the mother’s circadian rhythm. Our sleep cycle is tied to the cortisol cycle, cortisol being an important hormone that gives us a sense of wellbeing and that reaches its minimum level at midnight and peaks in the morning when we wake up full of energy and enthusiasm. What happens in the fetus’s late afternoon? The fetal pituitary gland, on feeling the gradual waning of the mother’s cortisol, switches on and stimulates the fetal adrenal glands, which start producing cortisol. This gives the fetus energy and a sense of wellbeing, so it starts “dancing”. In the morning, when mother’s cortisol is high, the fetal pituitary gland falls silent, fetal cortisol is low and baby sleeps in peace.

Thirty-second week of pregnancy: your baby is growing

In the thirty-second week of pregnancy the fetus has now reached a viable weight of nearly 2 kg (4.8 pounds) and continues to grow nearly 200 g (half pound) a week. This period of growth will determine weight at birth. As well as growing, that will enable him to handle autonomous life after birth are continuing to develop. Liver function is increasingly efficient and the lungs start to produce the surfactant liquid that will prevent their sponge-like alveoli from collapsing at the end of expiration. The fetus’s immune system is also gaining strength and being enriched by mother’s antibodies, transmitted via the placenta, which will help protect from an external environment rich in bacteria, viruses and fungi In the event of premature birth, the fetus’s chances of survival are excellent if good neonatal care is readily available.

The mother to be

In the thirty-second week of pregnancy everything contributes to generating a conspicuous transfer of liquids via the vein walls: the increased amount of blood in circulation; progesterone, which dilates the venous circulation; and the weighty uterus which hinders the venous blood return to the central venous circulation. The result? Her feet, downstream of all this, begin to swell. Remedies? The most effective is elastic socks or stockings, followed by resting with the legs elevated and stretched out. Rarely, the healthcare provider may recommend other substances to inhibit enlargement of the veins. Many women are also disturbed by the development of varicose veins.

Important to know

Working mothers-to-be should learn what their maternity leave policies are and decide when they would like to begin their maternity leave. Some employers may have flexible work-from-home policies; most jobs cannot accommodate this however. When a pregnancy is progressing without problems, the mother may stay at work as long as she likes. These decisions are often influenced by a family’s financial and other considerations. . Tips: Now is a good time to talk with your healthcare provider about your delivery plan and to be prepared in case labor begins unexpectedly. 

Thirty-third week of pregnancy: the fetus is growing

At thirty-third week of pregnancy, depending on growth potential and placental efficiency, the weight of the fetus in this final phase of pregnancy may differ from 0,5-1 Kg (1 – 2 pounds) with respect to actual birthweight. Males tend to weigh slightly more than females. Development may now be considered completed and the head is in proportion to the rest of the body.

The mother to be:

The size and weight of the belly are considerable, even more so in the case of twins or babies in the breach position. The fetal head should start to lodge deeply in the pelvis. The mother to be may have the sensation of feeling the fetus’s head between her legs. This is because the neck of the uterus, especially if made thinner by previous vaginal births, transmits this mechanical effort by pressing anteriorly on the bladder and posteriorly on the rectum. Even if the mother has lots of energy, doing all her typical activities may become difficult. Driving may even be a challenge: even with the seat put far back and reclining, it’s difficult for some women to find sufficient room behind the wheel. Even normal household chores get complicated, because the belly makes certain movements awkward, unbalanced, and cumbersome Simple tasks like dressing, undressing and bathing now require a lot of patience.

Important to know:

It’s time to make another decision that’s important for the baby’s future: should we or should we not take stem cells from the mother’s umbilical cord as a biological reserve of totipotent cells? There are pros and cons to weigh up here. During pregnancy the amniotic fluid and the blood in the umbilical cord are rich in stem cells. The possibility of taking a sample is therefore limited to  pregnancy, but the decision requires thought. Sampling and preservation have a high financial cost, while the potential benefits may never be required. Couples have to decide whether or not to take this opportunity

A pregnancy “at term” is a pregnancy in which birth occurs between the thirty-seventh week of pregnancy and 42nd week. This time honored obstetrical definition reflected the need to take account of women’s different ovulatory phases: a woman with 40-day menstrual periods ovulates and conceives on the 28th day and will therefore be “at term” some 14 days after a woman who ovulates and conceives on the 14th day because she has 28-day menstrual periods. In modern obstetrics, precise diagnosis of the time of conception by serial testing of the pregnancy hormone concentration in the woman’s blood and observation of babies adapting to extrauterine life have enabled the definition to be reviewed. We now talk of pregnancy being early term from the 37th to the 39th week, full term from the 39th to the 41st week, late term in the 41st and 42nd weeks and post term after the 42nd week. In a certain sense the term doesn’t just lapse but needs to be interpreted. What is the origin of these distinctions and, above all, how can we use our new knowledge in making clinical decisions? The first reason for these differences is that during fetal life the mortality risk is around one case in every 500 pregnancies, however impeccably monitored. The risk stays practically the same from the 12th to the 37th week, after which it starts to rise. This explains the obstetric practice of interrupting twin pregnancies in the 37th or 38th week, the disadvantages of premature birth being balanced with a stronger guarantee of survival. Another observation worth considering is that most scheduled births, especially cesarean, are performed in the 38th or 39th week so that the woman doesn’t go into labor before the scheduled date and so that an elective procedure (the woman isn’t having the contractions of labor yet) doesn’t become an urgent procedure because the woman is in labor. Elective procedures are safer for the mother and the fetus. But data on babies’ respiratory adaptation to extrauterine life show that it would be better to wait till the end of the 39th week because in the 38th and 39th weeks babies show twice the number of ventilatory complications compared to those born after the 39th week. The recommendation against delivering the fetus before the 39th week of prenatal life has solid scientific grounds but neonatal assistance can easily correct any difficulties in autonomous respiration. Great care must always go into balancing the advantages of an elective procedure against the risk of neonatal respiratory distress. Pregnancies going beyond the 41st week must always be carefully monitored because the risk of disappearance of the fetal heartbeat, even when the relevant parameters – clinical, ultrasound and cardiotocographical (ultrasound recording of fetal heartbeat and uterine contractions) – are perfectly normal, is always a possibility and without any warning sign such as a reduction in active fetal movements. The various national obstetrics and gynecology societies give different indications regarding monitoring and the most appropriate clinical approach in pregnancies going beyond the 41st week where the woman doesn’t go into labor spontaneously. After 200 years of modern obstetrics there are still doubts and perplexities about what optimal assistance for such women should be. Frank dialogue with a doctor to review the pros and cons of every decision is the best response to these still open issues. There seems to be consensus, on the other hand, on the necessity of inducing the birth of fetuses that reach and complete the 42nd week, because the risks attaching to further delay are clearly associated with a high probability of neonatal problems.

Thirtieth week of pregnancy: the fetus is growing

From the thirtieth week of pregnancy, interaction with the outside world also becomes more significant. Mothers may notice that the fetus reacts differently to certain foods and that certain pieces of music or movements stimulate more or less activity. In this period, the fetus’s muscular force is already considerable: assertive movements manifest its reaction to mom’s behavior.

The mother to be:

Acid reflux from the stomach to the esophagus is a common problem and often highly unpleasant. The common antacids, which are not absorbed, should be kept close at hand.

TIPS:  it’s advisable to talk with your doctor about medicines that reduce gastric acid secretion which causes heart burn. These medicines are generally considered safe to use in pregnancy. 

Important to know:

If the pregnancy is progressing uneventfully, no more ultrasounds are necessary at this point, so the things to do are: – routine obstetric appointments – routine blood tests: complete blood count, blood sugar level, serological testing for toxoplasma and cytomegalovirus antibodies in negative women – urine test to exclude the presence of sugar, protein and bacteria – the doctor may recommend additional tests if she has excessive swelling or any other unusual symptoms – some parents may consider whether, at birth, to take stem cells from the umbilical cord and cryo-conserve them for possible future use. Cost and family history are significant factors in this decision.

Thirty-sixth week of pregnancy: the fetus is growing

At thirty-sixth week of pregnancy, the average weight of a fetus is around 2.7 kg (aprox. 6 pounds) and its length is 40 cm (16 inches). At this stage in pregnancy fetus weight may vary considerably from woman to woman for genetic reasons. Two large parents will have bigger children than couples who are slightly built. This is easy to understand but it should be remembered that nature has regulated the fetal growth mechanism in proportion to the physical structure of the woman, including her pelvic dimensions, so that the fetus can usually be born without difficulty.

The mother to be:

Humans have paid a high price for their erect posture (bipedalism) because this type of ambulation has brought the pelvis bones closer together, making birth more difficult. To put this mechanical difficulty of birth in perspective, a 5-ton elephant gives birth to a calf of around 100 kilos (one fiftieth) and a 70-kg woman a fetus of around 3 kilos (one twenty-fifth). As if that weren’t enough, humans are the animals with the biggest brains in relation to their body weight, so the skull has had to grow bigger to accommodate the new part of the brain. The size of the fetus’s head and the narrowness of the pelvis explain why giving birth takes from 30 to 45 minutes for a second child and from 45 minutes to an hour and a half for a first birth. Evolution to the upright posture (bipedalism) and the increase in the size of the cranium (appearance of the cerebral gyri of the grey matter) occurred around 250,000 years ago and led to the shortening of pregnancy to allow for birth via the vagina. So it’s likely we humans are born prematurely, capable only of breathing air, controlling body temperature and being fed. What a huge difference from the offspring of other animals who can stand on their own legs a few minutes after birth and almost look after themselves. There is a great deal of biological significance in human pregnancy and women who are preparing for birth in these weeks may reflect on the biological privilege they have been given (that of giving life) but also on the modifications and difficulties that nature has undergone to perform this reproductive miracle.

Important to know:

Birth preparation courses are still in vogue. But are they really useful or can they complicate matters during childbirth? Many women wonder what will happen to them when they go into labor and whether they’ll be able to follow the obstetrician’s and gynecologist’s instructions properly. But no particular ability is required to give birth. The mechanism developed by nature enabling women to give birth operates in a sequence of spontaneous events that may, even today, be far from easy to control. So no particular skills or specific physical preparation are necessary in any phase of the delivery.  That being said, many women (and their partners) benefit significantly from childbirth preparation and educational classes.e.

A pregnancy “at term” is a pregnancy in which birth occurs between the thirty-seventh week of pregnancy and 42nd week. This time honored obstetrical definition reflected the need to take account of women’s different ovulatory phases: a woman with 40-day menstrual periods ovulates and conceives on the 28th day and will therefore be “at term” some 14 days after a woman who ovulates and conceives on the 14th day because she has 28-day menstrual periods. In modern obstetrics, precise diagnosis of the time of conception by serial testing of the pregnancy hormone concentration in the woman’s blood and observation of babies adapting to extrauterine life have enabled the definition to be reviewed. We now talk of pregnancy being early term from the 37th to the 39th week, full term from the 39th to the 41st week, late term in the 41st and 42nd weeks and post term after the 42nd week. In a certain sense the term doesn’t just lapse but needs to be interpreted. What is the origin of these distinctions and, above all, how can we use our new knowledge in making clinical decisions? The first reason for these differences is that during fetal life the mortality risk is around one case in every 500 pregnancies, however impeccably monitored. The risk stays practically the same from the 12th to the 37th week, after which it starts to rise. This explains the obstetric practice of interrupting twin pregnancies in the 37th or 38th week, the disadvantages of premature birth being balanced with a stronger guarantee of survival. Another observation worth considering is that most scheduled births, especially cesarean, are performed in the 38th or 39th week so that the woman doesn’t go into labor before the scheduled date and so that an elective procedure (the woman isn’t having the contractions of labor yet) doesn’t become an urgent procedure because the woman is in labor. Elective procedures are safer for the mother and the fetus. But data on babies’ respiratory adaptation to extrauterine life show that it would be better to wait till the end of the 39th week because in the 38th and 39th weeks babies show twice the number of ventilatory complications compared to those born after the 39th week. The recommendation against delivering the fetus before the 39th week of prenatal life has solid scientific grounds but neonatal assistance can easily correct any difficulties in autonomous respiration. Great care must always go into balancing the advantages of an elective procedure against the risk of neonatal respiratory distress. Pregnancies going beyond the 41st week must always be carefully monitored because the risk of disappearance of the fetal heartbeat, even when the relevant parameters – clinical, ultrasound and cardiotocographical (ultrasound recording of fetal heartbeat and uterine contractions) – are perfectly normal, is always a possibility and without any warning sign such as a reduction in active fetal movements. The various national obstetrics and gynecology societies give different indications regarding monitoring and the most appropriate clinical approach in pregnancies going beyond the 41st week where the woman doesn’t go into labor spontaneously. After 200 years of modern obstetrics there are still doubts and perplexities about what optimal assistance for such women should be. Frank dialogue with a doctor to review the pros and cons of every decision is the best response to these still open issues. There seems to be consensus, on the other hand, on the necessity of inducing the birth of fetuses that reach and complete the 42nd week, because the risks attaching to further delay are clearly associated with a high probability of neonatal problems.

Thirty-eighth week of pregnancy: the fetus is growing

In this thirty-eighth week of pregnancy the fetus completes its growth and development. It weighs around 2.8 kg (aprox. 6 pounds), measures 48.6 cm (19 inches), and its weight increases at around 30 g a day (1 ounce) . It has a cranial circumference of around 32.8 cm (13 inches). Its reflexes are coordinated, its bone marrow is starting to produce white blood cells and its liver is working.

The mother to be:

The final stage of pregnancy may bring certain problems with it. One of the lesser known but most bothersome of these is carpal tunnel syndrome. The carpal tunnel is a confined space beneath the wrist joint through which all the nerve endings of the hand pass. During pregnancy, this confined space has to deal with the considerable abundance of fluids in the mother, especially in the 3rd trimester. The more delicate and sensitive nerve endings of the tendons suffer compression by this abundance of fluid, which causes a sense of torpor in the hand or an irritating tingling feeling, both symptoms typical of a nervous disorder. How to combat this? The most useful physical exercises are those favoring the return of venous blood and lymph from the hands to the forearms. For example, she should try raising her hands above her head and clenching and opening her fists, or opening her hands fan-like and shaking them. Sometimes it’s useful to immerse the hands in tepid abundantly salted water.

Important to know:

Blood pressure must be constantly monitored throughout pregnancy. In the 3rd trimester, around 2-5 women in a 100 may experience a disorder in their arterial pressure regulation, with minimum values rising to over 90 and maximum values to over 140. When this happens, the doctor must immediately arrange for more frequent blood pressure tests. The exact origin of this disorder is not understood but we do know that it’s the placenta itself that generates it by not releasing the factors that determine the reduction in pressure needed for its own wellbeing. The resulting distress leads to the release of tiny fragments of placenta into the mother’s circulation. This “debris” deposits in the kidneys, where it’s eliminated but the filtering membrane is damaged in the process. The result is a loss of protein to the urine and potential kidney damage, even severe and persistent. In such cases the only cure is to induce birth and remove the placenta.

THIRTY-NINTH WEEK OF PREGNANCY: THE FETUS IS GROWING

In the thirty-ninth week of pregnancy thefetus has now reached full development. From the 39th week on its growth in terms of weight and length generally stops. The thick layer of vernix caseosa, a waxy white substance that has protected its skin throughout pregnancy in immersion, now detaches from the skin and collects in flakes that float in the amniotic fluid. This is why a fetus born at term is often pinkish and puffy, as if it had already had its first bath, while a preterm fetus may look floury, being covered with vernix. The amniotic fluid, which was previously nearly a liter and a half, has now been reduced to a few puddles around the fetus.

The mother to be:

From a psychological standpoint, the mother is probably in a state of pre-alarm in these weeks: she wonders whether she’ll be able to handle labor and tolerate the pain of the contractions. The main worry is about everything going well for her baby, that it will be born smoothly and above all healthy. Nowadays these fears, which are completely natural, are partly allayed by the numerous prenatal tests that can be carried out to monitor the fetus’s state of health.

Important to know:

The last prenatal exam focuses on the wellbeing of the mother to be and her fetus. This check includes:

• the obstetrical examination, which serves to assess the relationship between the dimensions of the fetus and her pelvis, the characteristics of the neck and opening of the uterus, and her general health
• ultrasound is sometimes necessary to check the quantity of amniotic fluid, the regularity of the fetus’s blood flow, the characteristics of the placenta and in some cases to confirm the position of the fetus established by the clinical examination
• routine blood tests in this final phase of pregnancy are of limited value if we are certain about the mother’s health and ability to successfully undergo labor and delivery. In some cases though, to ensure optimum care, it may be important to check that blood platelet levels and other coagulation parameters, liver enzymes, and renal function are all normal.

FORTIETH WEEK OF PREGNANCY: THE FETUS IS GROWING

In the fortieth week of pregnancy fetus has now finished growing. It’s around 50 cm long (20 inches) and weighs between 3 and 3.5 kg (7 pounds). In 96% of cases it is already positioned head down. 10% of babies are born after the 40th week. Thanks to the precision of the examinations and ultrasound that ascertain the start of pregnancy date, we now know that this is a real delay and not a late conception entailing a later term date. Not to worry though: consolidated tests and procedures can deal with this extra wait. The practice in the past was to wait patiently till the 42nd week and then induce birth. Unfortunately though, the percentage of cases with complications rose to nearly 50%. This is why the tendency is now towards a more prudent approach and in any case intervention by the end of the 41st week.

The mother to be:

In the 40th week of gestation, often the last before birth, the mother’s belly is large and heavy. The fetus has reached full intrauterine development and now occupies nearly all the cavity because the amniotic fluid has gradually diminished. In doing her daily routine, the mother should be even more careful in her movements.
Her center of balance is off and the belly tends to tip her forwards. Putting on shoes becomes difficult, so comfortable clogs may be preferable. Even finding a comfortable position, whether sitting or lying down, becomes difficult, if not impossible. All the changes to her body that have developed during pregnancy have now reached their maximum extent and her maximum tolerance. At the end of the day the mother to be may well feel very swollen too: her feet hurt, it’s hard to take off her rings, and her face may look round. After any false alarms she may have had in the previous weeks, uterine contractions now become significant, as they directly anticipate labor. Every now and again, activation of all the muscular cells generates a painful contraction. She waits to see if others will follow until the big moment comes.

Important to know:

When does labor start? All women in their first pregnancy are worried about not noticing that the birth mechanism has already started and not managing to get to the chosen clinic or hospital in time. In practice around half of 1st birth women turn up in maternity admission convinced they’re in labor and their waters have broken, whereas everything’s still on hold and they’re sent home with words of reassurance. So when is the right moment to go? When the waters break, even if painful contractions haven’t started yet? The right time is when contractions are both very painful (preventing her from walking or talking at the height of the contraction) and periodic (the interval between one and another is of near stopwatch precision). Isolated and not too acute contractions are merely signs of pre-labor.