Fetal brain development

The article was consulted professionally by Dr. Nguyen Anh Tu – Doctor of Obstetrics ultrasound – Pre-birth diagnosis – Obstetrics department – Share99 Hai Phong International Health Hub.

Fetal brain development from within the womb is a very magical process. As early as the 3rd week of pregnancy, the baby's brain has begun to form, develop and constantly improve until the fetus is born.

1. Structure in the brain of the fetus

Structurally, the human brain is divided into 5 different regions, each of which is responsible for each function separately, including:

  • Great Brain: This is the largest part of the brain, responsible for thinking, remembering and feeling. The great brain is also where the cortex and lobes reside, including the frontal and temporal lobes.
  • Cerebral palsy: This area coordinates movement, maintains the position and creates a sense of balance.
  • Brain body: Is the center that controls many of the most important functions, including heart rate, breathing rate and blood pressure.
  • Saddle glands: Pea-sized, in charge of releasing hormones into the body, supporting growth, metabolism and performing a number of other functions.
  • Downhill: The area is associated with body temperature, feelings of hunger and thirst, sleep and emotions.

2. First Trimem: Baby begins to move

Only after 16 days of conception, the nervous background of the fetus begins to form, growing in length and with folds. They then turn into a groove and then gradually create a nervous tube.

Around the 6th-7th week of pregnancy, the nervous tube closes in a curved direction and divides into three parts, including: the forem, the middle brain and the back brain. The spinal cord will soon appear in the adjacent part of the brain. Shortly there followed, the fetal brain development also originated in the nervous tube and divided into 5 areas as listed in section 1. However, all areas of the fetus' brain still need more time to continue to mature completely.

Also during this period, several special neurons are present and move throughout the embryo to create the first nerves. The baby's nervous system consists of millions of neurons; in each of these microscopic cells there are branches for them to connect and transmit information to each other. Basically, the first synapses also form and produce early fetal movement, such as curling up in the right place.

Some other movement also quickly takes place, the fetus can wiggle the limbs and begin to develop touch at the 8th week. At the end of the first trimep, the baby is already capable of performing quite a lot of action although the mother has not yet been able to feel it.

3. Second trimen quarter: Reflexes

In the second trimepcle, the fetal brain plays a role in controlling regular contractions in the diaphragm and pectoral muscles, similar to breathing movements. At the same time, a protective layer that increases the rate of signaling between neurons, called myelin, will appear and cover around the baby's nerves. Myelin will continue to develop until the child is one year old.

  • Week 16: The baby knows how to feed and swallow for the first time.
  • About week 18: I started noticing my baby's first pedal. However, the first step may also be a few weeks late, especially in first-time pregnant mothers.
  • Week 21: Natural reflexes cause the baby to swallow several tens of mL of amniotic fluid per day. This action will help the taste buds gradually develop more completely.
  • Week 24: Another noticeable reflex occurs, which is that the baby knows how to wink.
  • Week 27: When the second trimemep ends, the baby's nervous system continues to mature.

At the last stage of the second trimep, the brain trunk of the fetus is almost completely mature. They are located just above the spinal cord and below the cerebral cortex – the last mature area. At this time, the fetal nervous system has developed enough for the baby to startle if there are loud noises outside the uterus, or can even turn his head toward the voice of a loved one. If you want to use music that stimulates the fetal brain, this is the right time.

16th week fetus

At week 16, the baby will know how to feed and swallow for the first time

4. Third Trimemen: Brain Development

At week 28 of pregnancy, the central nervous system can control rhythmic breathing and control body temperature. In particular, the baby's brain wave activity has appeared sleep cycles, including the stage of having a dream. When did the fetal brain thrive? The third trimepcle is the stage in which the cells and nervous system grow most rapidly, namely:

4.1 Mass

Fetal brain development tripled in weight in the last 13 weeks of pregnancy, from about 100g at the end of the second trimepcle to nearly 300g at this time.

4.2 Surface

The surface of the brain also looks different, no longer as smooth as it used to be, but more and more grooves and wrinkles, similar to the image of the brain is often seen.

4.3 Minor brain

The primary brain , which controls movement, is the most rapidly growing area of the entire brainof the fetus , with a surface area that increases by 30 times in just the last 16 weeks of pregnancy.

4.4 Cerebral cortex

Although the most important area of this brain still develops rapidly during pregnancy, the cortex only really begins to work around the time the baby is close to being born. The cerebral cortex will continue to mature in the first few years of the baby's life thanks to the diversity of the environment in the outside world.

5. Good diet of fetal brain development

The importance of Folic Acid for pregnant women

Folic acid and group B vitamins are essential for fetal cell growth, tissue and DNA

5.1 Folic acid/B vitamins

Since the baby's nervous system begins to develop at the beginning of conception, it is recommended that women add 400 micrograms of folicacid , also known as B vitamins, every day from the moment they intend to become pregnant.

This nutrient is essential for fetal cell growth, tissue and DNA. Research shows that early supplementation of this type of substance in full pre-pregnancy will help reduce the risk of severe malformations of the nervous tube by 70% and 40% of babies born with autism spectrum disorders. Therefore, take B vitamins before birth (at least 400 mcg) and make sure to eat more foods rich in folic acid, including greens and whole grains.

5.2 Omega fatty acids

Specifically, DHA, also known as docosahexaenoic acid, is also important for the development of the eyes and brain of the fetus. Since it is the main structural fat in the brain and eyes of the baby, it is essential to adequately replenish omega-3 fatty acids, especially at the stage when the brain development of the fetus takes place most strongly (the third trimepcle). DHA is found in a wide variety of fatty fish and cold-water fish such as: salmon and cod. In addition, consuming seaweed together with eggs also adds an amount of DHA to the body.

Share99 International Health Hub offers a full maternity care program for women from the very beginning of pregnancy from the first months with a full range of pregnancy examinations, 3D ultrasounds, 4D routines and routine tests to ensure the mother is always healthy and the fetus develops comprehensively. In addition to regular visits, women will also be consulted on nutrition and exercise so that the mother can gain weight properly and the fetus still absorbs nutrients well.

Dr. Nguyen Anh Tu has 6 years of experience in obstetrics and gynecology ultrasound, especially researched and trained in pregnancy ultrasound – pre-birth diagnosis. Dr. Tu has completed courses on ultrasound – pre-birth diagnosis of the FMF International Society of Fetal Medicine; be trained in consulting and implementing diagnostic intervention techniques in fetal medicine and participate in many in-depth conferences and seminars on Fetal Medicine. Currently a doctor in obstetrics and gynecology department of Share99 Hai Phong International Health Hub.

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Article reference source: Whattoexpect.com; Ncbi.nlm.gov; Mayoclinic.org


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About: Minh Quynh

b1ffdb54307529964874ff53a5c5de33?s=90&d=identicon&r=gI am the author of Share99.net. I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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