9 months 10-day journey in the womb of the fetus

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.

The journey of 9 months and 10 days of fetus development in the womb is magical. Surely you will always want to know what the process of your child is growing, how you are developing?… This article will tell mothers the formation and development of the fetus by week.

1. Stage 1: Embryo formation

Leg 1: When the enlarged vagina has a highly acidic environment, more than 60 million sperm are passed through the vagina and can reach the woman's cervical.

Stage 2: In the cervical there is a layer of mucus that makes it difficult for sperm to move. About 100,000 sperm remain able to overcome this mucus.

Leg 3:Sperm moves at a speed of 5mm/min and through the cervical in just 10 minutes. Leukocytics here see the appearance of strange characters so will destroy sperm. About 200 sperm left that can reach the ovulation tube

Leg 4: With 10cm of ovulation they need to pass to get the healthiest sperm to meet the egg

The strongest sperm will release the enzyme to create a membrane that protects the entire appearance of the egg, the egg at that time also closes all small holes. Now sperm and eggs will be linked together into a ovulation.

Formation and development of the fetus

Embryonic formation

2. Phase 2: Fetal development over the weeks

  • 1-week-old fetus

The mucous layer of the uterus will be thickened to support and nourish the fertilized egg. This mucous layer will follow the blood out during the next period if fertilization does not take place.

  • 2-week-old fetus

Conception usually takes place in the ovulation tube, but of course the mother will not recognize this because there is no manifestation outside.

2.1. First trimemep

The first 3 months of pregnancy is when the mother will see her body appear new changes. Fetal development during this time is usually very slow because the baby is building an important foundation for development in the following months.

  • 3-week-old fetus

This is the moment that confirms the successful conception of the mother. Entering the 3rd week of pregnancy, you will see the first sign of a week's delay. Fertilized eggs form the este, the prince will move gradually into the mother's uterus to choose the best "dwelling" for the upcoming 9-month process. The pregnant mother's body will receive signals and secrete more Oestrogen and Progesterone, which will help maintain and nourish the baby throughout pregnancy.

  • 4-week-old fetus

The pregnancy is still ongoing and some mothers may not even know they are pregnant. Fertilized egg cells are nestled inside the lining of the uterus shaped like a balloon with hundreds of small cells that will grow into the fetus later. The embryo will begin to produce the pregnancy hormone hCG – the hormone that prevents you from ovuling monthly. Moreover, the embryo will begin to act the cells to create the initial structure of the fetal body.

  • 5-week-old fetus

At the 5th week of pregnancy, the embryo is officially formed. It's been 4 weeks since you started your last semester. Entering week 5, you can identify yourself as pregnant through a few signs of early pregnancy. The 5-week-old fetus is only as large as a small dot, however this size is already 10,000 times larger than when the new mother conceived. And also during this week of pregnancy, in turn the signs of pregnancy will appear so that the mother can be more sure when using the pregnancy test stick.

  • 6-week-old fetus

This is the right time to perform your first pregnancy visit. The fetus at the six-week-old milestone was shaped and measured through ultrasound. The doctor will measure the average length of the pregnancy bag will be about 5-6 mm. The size of the fetus at this time is about 1cm, which is equivalent to apple seeds and looks like a tadpole but this is a stage when the baby grows very quickly. The arythal system and the bone system begin to form, the little heart will begin to have a beat.

  • 7-week-old fetus

At the 7th week of gestation, the fetal heart rate is clearly visible through ultrasound. You can go for an ultrasound so that your doctor hears your baby's heart rate, the first sign that a living germ is growing in your heart. My baby was as big as a pea. This week, she focused on brain development. In addition, the liver is performing the function of producing red blood cells until the bone marrow is formed. In addition, parts such as the nose, mouth and ears begin to shape. This is a very special week, marking the moment when you start to have sick bouts.

Formation and development of the fetus

7-week-old fetus
  • 8-week-old fetus

Your baby has officially been called a fetus with a length of about 1.5cm. The size of an 8-week-old fetus is already twice as large as week 7, but the baby still has a tail behind it. This tail will soon disappear. The baby's legs and arms look like paddles that are gradually being shaped. Heart valves, air duc duc ducs from the throat to the lungs have also formed. Fingers, toes and feet as well as lips, the baby's eyelids gradually become clearer. At the 8th week of pregnancy, the baby is as big as a blueberry.

  • 9-week-old fetus

The 9-week-old fetus is about the size of a grape, about 2.3cm long. The baby's genital system is gradually formed but it is not until the 15th-17th week that the fetal sex can be predicted correctly. The baby's mouth and tongue are formed this week. Hands at the moment are also divided into fingers. Your baby begins to have movement but she is too small to feel these motions. Neurons are branching and forming the first nerve ducges.

  • 10-week-old fetus

The fetal heart is divided into four cavities and the fetal heart can be heard measured by Doppler ultrasound waves. All parts of the baby have developed but the brain is still large and the digestive system is still in development.

Basically, the 10-week-old fetus has developed in the right place, even developing tiny earlobes but there are still many more parts that will grow later. By week 10, the embryonic tail had disappeared, the size of the fetus was as large as a cherry.

  • 11-week-old fetus

The baby's ingica forms at the 11th week but to finish it still needs a little more time. The baby's hand begins to move and clutches into the shape of a fist. Meanwhile, the brain and nervous system are still on the way to great development. Although genitals have been formed, it is still too difficult to determine the sex. This week, tooth buds have also grown and eyes are fully formed, throughout the baby's body there are more clear hairs and faces. At this time, the baby is as big as a strawberry.

  • 12-week-old fetus

This week when I can see how your form has been tough and a lot more baby-shaped. The central nervous system, heart and liver and excreted system of the baby have basically perfected the functions. A 12-week pregnancy is also an important pregnancy ultrasound timeline for doctors to monitor the gestational heart rate. Healthy fetuses will have a heart rate of 120 – 160 beats per minute. The size of a 12-week-old fetus can be as large as a lemon.

  • Fetus 13 weeks old

At week 13, your baby will have internal reflexes such as fingers that can spread or shrink, foldable toes, and mouths that act like suckers, but you still can't feel your baby's activities. The baby is about the size of a plum and can feel the external effects as you gently poke on the abdomen. By this week, the baby has shown special signs of recognition – fingerprints. Not only that, she also frowns, grimaces when in the womb.

Formation and development of the fetus

In week 13, your baby will have internal reflexes such as fingers that can spread or shrink

2.2. 2nd Trimem

The 2nd trimep of fish from weeks 14 to 27 is considered the most stable stage of fetal development. The highlight of these 3 months is that the fetus will develop bones, muscles and mothers can see their baby's face more clearly through ultrasound footage.

  • 14-week-old fetus

Fetal size and weight from week 14 1 2017 will have significant growth. On average the fetus will increase by about 2 grams a week. The fetal central nervous system has grown to several million cells, the genitalia of which are also being formed more specifically this week.

  • 15-week-old fetus

At 15 weeks of gestation, the fetus is about 10.1cm in length and weighs about 70 grams – the size of a small apple. Although the baby's eyelids are not yet open, they can already see if there is light passing through the womb. The baby's brain impulses begin to work and the baby also begins to have facial muscle movement. The kidneys also begin to work in week 15. If you have an ultrasound, you will see an image of your baby sucking his finger. The 15-week-old fetus is already as large as a peach.

  • Fetus 16 weeks old

The 16-week-old fetus has been much tougher thanks to the growing bone system. Therefore, pregnant women need to replenish calcium every day as well as apply appropriate methods of pregnancy to support their child's brain development.

  • Fetus 17 weeks old

The baby may have moved the joint and the sweat glands are also more developed. The size of a 17-week-old fetus from head to butt is about 13cm and weighs about 140 grams. The 17-week-old fetus is as old as an avocado, the details on the scalp gradually appear but have not yet seen the hair. The leg has grown more and you can feel this through your baby's pedals. The baby's head is straighter and the ears have gradually shaped the correct position.

  • 18-week-old fetus

The baby's body has been more balanced with the 3 3 20s that have grown evenly with the body, several strands of hair have begun to undulate on the baby's head. Week 18, the fetus is as large as a pomegranate and can move joints and skeletons formed from soft cartilage that has hardened. The umbilical cord grows firmer and thicker.

  • 19-week-old fetus

She can even feel her heartbeat beating every beat inside her body. The fetal genitalia had been complete since the previous week so if the ultrasound is this week, the mother can fully know the sex of the fetus. She was as big as an artichoke. Your baby can fold his legs and you will feel this movement. Myelin nerve sacks are gradually forming around the nerves.

  • 20-week-old fetus

Baby up to 300 grams this week and head-to-butt measurement length is 16.4cm. The fetus is still swallowing amniotic fluid very actively to practice for later digestive activity. Your baby's eyes are still closed, but some movement in the uterus can take place during the 20th week of pregnancy.Week 20, the senses such as: smell, sight, touch, taste, hearing are developing and the baby can hear what you say. At this time, the baby is already as big as a mango.

Formation and development of the fetus

20-week-old fetus
  • 21-week-old fetus

The fetal jawbone will be formed this week and the baby's arm and leg muscles are also much tougher for the baby to prepare for the stage of pregnancy. By the 21st week, the baby's hair and eyelashes begin to grow. At the 21st week of pregnancy, the fetus can swallow amniotic fluid, and the digestive system begins to produce black, thick stools that the baby after birth. This week, the baby is about the size of a banana.

  • 22-week-old fetus

At the age of 22 weeks, the baby has posed as a newborn baby. The 22-week fetal weight is about 430g and has a head and foot size of 26.7cm, which is equivalent to a small pumpkin. By this week, the baby's pedaling and turning are much stronger and make her more likely to see a sharpness in her abdomen.

  • 23-week-old fetus

The baby's nostrils this week have passed rather than closed as they did in previous weeks. Besides, the lines on your face have become very clear and your body has also become much more rounded. At 23 weeks, the fetus looked like a newborn with a complete part but was small because she was only as big as a coconut, but eye color pigmentation has not yet appeared.

  • 24-week-old fetus

You're halfway through pregnancy. This week, the first amount of fat will accumulate under the fingers and palms, legs of the baby. The baby's skin begins to stretch to accumulate fat gradually until the baby is born.

The fetal nervous system will grow tremendously this week, your eyes have started blinking, your ears have heard your parents' voices, and the senses have been much sharper. In particular, you will be surprised to feel the phenomenon of pregnancy. This week, the first amount of fat will accumulate under the fingers and palms, legs of the baby. The baby's skin begins to stretch to accumulate fat gradually until the baby is born. At this time, the baby is already as big as a grapefruit.

  • 25-week-old fetus

The baby's skin at this stage is still very thin and the mother can see her blood vessels when she has 3D, 4D ultrasound. The baby is weighing about 660 grams and the length from head to toe is about 34.6cm. At 25 weeks, the fetus looks quite long and sick but in fact protein is actively replenishing to make up the baby's flesh. The baby's skin is still thin and translucent but this will soon change. The 25-week-old fetus is as old as a melon.

  • 26-week-old fetus

The 26-week-old will maintain plenty of naps to perfect her vision as well as her brain. At 26 weeks, the baby grows with a cauliflower, his wrinkled skin gradually stretches because the fat inside the skin is gradually forming. This helps babies look more like babies. Hair begins to grow and has a color, texture. The baby's weight at this time is about 900 grams. The baby's head is already proportional to the body and looks almost identical to normal. There is a lot of development in the brain that takes place during sleep.

  • 27-week-old fetus

This week the pregnant mother's baby weighed an additional 300-400 grams. Most of the time the fetus will sleep to save energy and accumulate the necessary fat for the body. At week 27, the baby is as big as a kale. The baby will inhale the amniotic fluid to help the lungs grow. This breathing activity is an exercise in preparation for breathing air after birth.This is the moment when the fetus is most hyperactive with strong movement. This proves that the baby is healthy and very well developed.

Formation and development of the fetus

Most of the time the fetus will sleep to save energy

2.3. 3rd Trimem

The development of the fetus in the last 3 months of pregnancy is mainly about maintaining and developing weight and perfecting the shortcomings for the baby to prepare for birth. Pregnant women should be aware of the risk of premature birth, gestational diabetes or pre-maternity seizures … it is very easy to happen if your health is unstable.

  • 28-week-old fetus

This week, the baby's brain is growing at a fast pace so pregnant mothers should eat a variety of foods that are good for the brain such as fish. The fetus now weighs about 1kg and almost the baby has lived a separate life inside the womb. The baby's head was smaller with an almost complete developed brain, his hands and feet were strong enough to be able to throw kicks into the womb wall. The fetus still constantly swallows amniotic fluid and absorbs fat to accumulate fat to protect body temperature. At this point, I grew up with a cabbage tree.

  • 29-week-old fetus

At week 29, the baby's vision continues to grow and he can feel the light from the outside. Your baby may blink and your eyelashes will grow even more. Fetal vision is now 1/20 and will continue to develop further in the following weeks. He has gradually remembered the voice of his father and his mother if he or she spends time every day talking to him.

  • 30-week-old fetus

The activity of closing and opening the baby's eyes has become very flexible this week. The baby's head is also larger so that the brain has space to grow. The lungs and muscles work more to prepare for function in the outside world. The baby will still sleep most of the time. When the baby is awake, the pregnant mother will see her belly rise and fall down in the positions where she is moving as well as feel the pushes of the knees or elbows on the wall of her abdomen, or the steady hiccups of the baby inside.

  • 31-week-old fetus

The baby's lungs are complete by the week of pregnancy 31, so if he is born at this time, he can still breathe on his own. The size of the baby is already on par with a siamese coconut with a length of about 41.2 cm and is surrounded by 1.5 liters of amniotic fluid. As the baby is older and takes up a lot of space inside the uterus, the amount of amniotic fluid decreases. Babies are starting to accelerate and gain weight very quickly this week.

Formation and development of the fetus

The size of the baby is already on par with a siamese coconut
  • 32-week-old fetus

The development of the fetus at this stage witnesses the process of rotating the fetus of the baby. From this week 32 until the mother gives birth, the baby's weight will not change significantly. A layer of fat that protects the body is formed under the skin and makes the baby's limbs dust more dusty. It is not until a few months later that the baby can make conscious and purposeful gestures. The movement and rest of the fetus at this time in a fairly regular cycle.

  • 33-week-old fetus

My weight is about 2kg at the moment and the length measured from head to toe is 43.7cm. The baby's body temperature has also been more stable and no longer depends much and the mother's body temperature. The baby's brain still grows at a dizzying rate. Therefore, pregnant mothers should continue to strengthen foods rich in DHA. Now, the 33-week-old fetus is as big as a pumpkin.

  • 34-week-old fetus

The first amount of stool has been formed in the abdomen of the baby. The skeleton has gradually improved and is much stronger, except for the skull bone is still soft to facilitate the later birth of the baby. At week 34, the bone composition in the skull has not yet been edested, but it makes it easier for the fetus' head to pass through the vagina. This means that pregnant mothers are easier to breathe, but the pressure on the bladder is heavier. The 34-week-old baby was as big as a large turkey.

  • 35-week-old fetus

At 35 weeks gestation, the baby weighs about 2.3kg and is 46.2cm long. The parts of the baby's body have mostly fulfilled their functions. Therefore, if there are no health complications, the baby will remain healthy if born this week. The central nervous system as well as the lungs are gradually improving. Babies born between weeks 34 and 37 can develop independently, without health complications, they can be healthy.

  • 36-week-old fetus

The fetal weight this week will be about 2.6 kg, and the size from head to toe is 47 cm. At 36 weeks, babies growing up with pineapple should feel cramped in the uterus. The baby's kidneys are fully developed and the liver has been able to excrete unnecessary substances. Most of your baby's muscles are complete, except that the brain and lungs will continue to grow until they grow.

  • 37-week-old fetus

At this time, the fetus has turned its head and will not stop ramming its head towards the mother's pelvis. At week 37, every day the baby increases by about 30g. The baby's body will form a layer of white wax, called caseosa vernix to protect the skin. At this time, the baby is as big as the papaya. If the baby wants to be born this week, this will be a premature birth that does not affect the health of the baby much.

Formation and development of the fetus

37-week-old fetus
  • 38-week-old fetus

By week 38, the day of the crossing is approaching, although the baby already looks like a newborn, but he is not ready to step out into the outside world. Over the next two weeks, the lungs and brain will develop more fully. The 38-week-old fetus is considered the last week of pregnancy in the normal gestational cycle. The baby's subcutaneous fat layer will continue to grow a little thicker to keep the baby's body temperature stable after birth.

  • 39-week-old fetus

At 39 weeks of gestation, activities such as hand sucking, breathing, sucking, digestion, excretion, crying,… will take place very naturally from this time until the baby is born. Babies are also considered to have enough days and months, but in some cases they are not really ready to go out and see their parents.

  • 40-week-old fetus

At week 40, the development of the fetus physically is complete but the baby continues to produce the amount of fat needed so that the body can adjust the temperature at birth. Babies 40 weeks old with large pumpkins.

3. Stage 3: Welcoming babies

When the baby is born, you will see that the baby is connected to the mother by umbilical cord up to 50cm in length. Through the umbilical cord, all sources of nutrition as well as oxygen will be transmitted from mother to baby and then the waste from the baby also through the umbilical cord to the mother's excretion system.

After the baby is born, the umbilical cord is cut off, leaving about 2 to 3cm of the part directly connected to the baby's navel. After gradually, the umbilical cord will dry out and then fall out on its own, forming the baby's umbilical cord, the navel will grow like a normal person. Today, the method of laser umbilical cord cutting immediately after birth is also applied in many institutes, safer and avoids more infections.

The first week after birth is an important period, at which point you begin to get used to the new environment with many surprises and difficulties. The first month after birth is the newborn stage, which at this time is the most dangerous of life, with the highest risk of death.

The journey of 9 months and 10 days of pregnancy is magical and many surprises. Share99 International Health Hub currently has packages of maternity health care packages with outstanding quality. Pregnant women are supported by an experienced obstetrician and gynecologist at Share99 during pregnancy – labor – post-birth. Maternity packages at Share99 International Health Hub include:

  • 12-week maternity package
  • 27-week maternity package
  • 36-week maternity package
  • Package maternity – labor

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 at Obstetrics and Gynecology Department of Share99 Hai Phong International Health Hub

For direct advice, please click hotline number or register online HERE. In addition, you can register for remote consultation HERE


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About: John Smith

b1ffdb54307529964874ff53a5c5de33?s=90&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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