Pregnancy month by month

We know that every mother would like to see her baby grow in her tummy and with this video full of models, animations and ultrasounds, Dr. Carlos Monsalve, an expert in maternal-fetal care at Creafam, explains to us week by week and month by month the development from embryo to fetus and baby.

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We know that every mother would like to see how her baby grows in her tummy, so today we are not going to talk about care, studies or recommendations for pregnancy. We have made a video that will allow you to see everything that happens in your baby’s little world in the safety of your tummy, so enjoy it and remember that knowledge is power

It is important to make it clear that the weeks of pregnancy do not begin to be counted from fertilization because unless in vitro fertilization is performed, it is practically impossible to know the exact moment of fertilization. In obstetrics we start counting from the first day of the last menstruation you had, so in this video every time we say “weeks” of gestation we mean from the first day of your last menstruation.

Fertilization and embryonic stage, weeks 2 to 9

We know that ovulation will occur around 14 days after your first day of menstruation, but once the egg is released from the ovary it will still take a couple more days to reach the fallopian tubes and meet the sperm. Once the sperm penetrates the egg, they combine into a single cell called a zygote. As soon as the zygote begins to divide, it will become an embryo.

The embryo will continue to divide and travel through the fallopian tubes until it reaches the uterus. Many mothers have asked us “When will I start to feel pregnancy symptoms since I had sex yesterday?” Remember that until now the embryo has not implanted in the uterus so it is impossible for a woman to detect any symptoms of pregnancy, but in the middle of week 3 the embryo reaches the uterus, implants and begins to release hormones, mainly the hormone chorionic gonadotropin, this is the hormone that is released only during pregnancy and now the mother can begin to feel the typical symptoms of pregnancy such as nausea, fatigue, mood change, although each case is unique and there are women who They do not present these symptoms throughout the pregnancy.

We are going to talk about the size of your baby during pregnancy and sometimes we do not perceive it so well in centimeters or millimeters, so we are going to compare it with fruits and seeds. By week 4 she is the size of a poppy seed. The most obvious symptom arrives: The absence of the period, and the mother may begin to suspect something and although we do not detect it on the ultrasound, the embryo already has a heart. Right now it still looks very strange, elongated and without limbs, it has a yolk sac from which it will feed until the placenta begins to function. Don’t worry about missing a heartbeat or being told it’s too small or not growing properly. It is too early to detect it, even if you do not know exactly the moment of fertilization, you can go for a consultation in very early stages and not even detect the pregnancy sac, do not worry about this, you always have to give it a chance. growing and follow up with ultrasound or hormonal monitoring. Its tissues begin to divide into three layers: The outermost layer or ectoderm will become the brain, the middle layer or mesoderm that will form most of the body and the inner layer or endoderm that will soon be the respiratory and digestive system.

In week 6 it is the size of a small rice. We will observe and listen to the heartbeat, we at Creafam, having advanced equipment, can sometimes detect it between weeks 5 and 7. Folic acid is essential for the formation of the neurological system, so the ideal is for the mother not to wait until this moment to start taking it, remember from three months before achieving pregnancy and throughout the first trimester you must take folic acid. In week 7, a blueberry.

Fetal stage from week 10

From the second month we no longer call it an embryo, in week 10 the fetal stage begins, it measures about 3 or 4 centimeters and we can already distinguish the outlines of arms and legs, rudimentary structures in the brain, although the neural tube is not yet there. closed and the abdominal wall may present a physiological hernia, do not be afraid, it is normal and will close until week 12.

In week 11 it is the size of a fig. Around week 11 or 12 we can distinguish facial features such as the eyes, the formation of the ears, nose, mouth, jaw bones, already complete limbs of arms and legs and as we mentioned, the abdominal wall completely closed and we observe the Skull bones also completely closed, genitals, liver, eyelids and even nails appear. From week 12 the second trimester begins and now he really does look like a miniature baby. In week 15 it already looks like an apple.

Around week 15, that is, three and a half months, babies begin to swallow, they begin to swallow their own amniotic fluid and they swallow it and urinate it. By the fourth month, the fetus is covered with fine hair called lanugo that may be more visible on the eyebrows and upper lip. It can begin to make fine movements such as opening and closing its hands.

Mid-pregnancy, at week 20

Para la semana 20 tiene el tamaño de un coco, hemos llegado a la mitad del embarazo a partir de la semana 20 el feto mide de 18 a 20 centímetros y pesa alrededor de los 300 gramos. El cerebro, músculos y órganos continúan su desarrollo entonces los cambios comenzarán a ser menos en el aspecto físico y un poco más en su capacidad de sentir y reaccionar al ambiente.

Ahora si la madre comenzará a sentir las primeras pataditas y con un equipo que incluso ya nos pueden vender en las farmacias, que es un equipo doppler, pueden escuchar sus latidos cardiacos. En la semana 24 su tamaño se compara a un elote. Para el sexto mes el bebé empieza a responder a los sonidos y por eso muchas mamás empiezan a ponerle un poco de música o hablar directamente a la pancita, pueden incluso reaccionar con movimientos súbitos ante un ruido fuerte y podríamos decir incluso que se asustan de los ruidos fuertes pero en realidad es sólo que ya pueden reaccionar ante estos estímulos. En la semana 27 tiene el tamaño de una coliflor.

Para el séptimo mes ya pesa un kilo y medio más o menos y además de reaccionar a los sonidos también ya empieza a reaccionar a los estímulos luminosos aunque como ya es más grande y el espacio empieza a quedarle el pequeño ustedes van a notar que los movimientos son menores, pero claro siempre es importante que su bebé se esté moviendo con que ustedes perciban movimientos en la mañana mediodía, tarde y noche será suficiente para que ustedes sepan que su bebé está bien.

Hace muchos años existía una escala para medir la cantidad de movimientos del bebé, supuestamente entre más se moviera iba a ser un bebé más sano, hoy en día sabemos que eso no es cierto. Lo importante es percibir que tu bebé se esté moviendo durante el transcurso del día y el dato de alarma sería si bruscamente disminuye esos movimientos. Por el contrario cuando un bebé se está moviendo de más y hasta les duele los golpes que genera el bebé no se preocupen, no significa que esté incómodo, significa que le está llegando suficientemente bien el oxígeno para tener esa vitalidad.

Preparing for childbirth, week 33

By week 33, which is already seven and a half months, it is the size of a pineapple. The baby assumes a position with its head down, fitting into the pelvis and at the same time putting pressure on the bladder, so the mother will surely have the urge to go to the bathroom very often. Although she cannot breathe yet, her diaphragm begins to move imitating the respiratory movements that are necessary to breathe at the moment of birth, strengthening and preparing for that moment.

By the eighth month the baby is almost ready to be born and in case of premature birth she has a very good chance of being born without any problems. Most of the lanugo falls out, only a little is usually left on the shoulders and the hair begins to get a little thicker, even in the ultrasound we can see if he will be born with a lot or little hair. At nine months the testicles of male babies should have descended,
If it is a baby girl, the vaginal lips will already be completely formed. By week 39, he is already a full-term baby, who does not have much growth left because he already has the size and even weight of a watermelon.

The baby already has periods in which he stays awake and in which he sleeps and although we do not know for sure, he must surely dream something. There will be babies who by week 40 already look like big November pumpkins, at 40 weeks the baby already weighs around three kilos, some more, others less and measures on average about fifty centimeters but its size can definitely vary, in addition The most likely thing is that the baby will come before or after the calculated delivery date, do not worry about this, only in 5% of pregnant women, the baby is born on the calculated delivery date.

You just have to be a little careful, when a baby is past 40 weeks the visits will have to be more continuous, because it is also very common for a baby to be post-mature. But whether you decide to have a cesarean section or a humanized birth, remember: At Creafam they have a team of specialists to accompany the mother and protect the baby on the day of birth. With great affection, we wish you a very happy pregnancy and a dream come true.

“Do not worry if in the first weeks you go to the consultation and do not detect the embryo or if it is very small, it needs the opportunity to grow and follow up”

Dr. Carlos Monsalve
Dr. Carlos Monsalve
Specialist in gynecology and obstetrics

Perinatology, invasive techniques and obstetric ultrasound.
Hospital Universitario La Fe, Valencia, España.

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