Signs of good fetal development in the second 3 months

This is an automatically translated article.

The article is professionally consulted by Specialist Doctor II Bui Minh Phuc - Department of Obstetrics and Gynecology - Vinmec Ha Long International Hospital.

The second trimester is counted from the 13th to the 27th week of pregnancy. In the second trimester, the sex of the fetus can also be clearly seen and the pregnant woman begins to feel the movements of the fetus.
Here are the signs of good fetal development in the second trimester:

1. 13th week: Urine is formed

The 13th week of pregnancy (equivalent to the 11th week after fertilization), the fetus begins to drink amniotic fluid and excrete urine into the amniotic chamber, yes, and drink again, forming a cycle!
The bones of the fetus begin to harden, especially the skull and long bones. Your baby's skin is still thin and easy to see through, but it will soon thicken.

2. 14th week: the sex of the fetus becomes clear

In the 14th week of pregnancy (equivalent to 12 weeks after fertilization), the fetal neck is more clearly shaped, and the lower limbs are also developed quite a lot. The fetal spleen begins to produce red blood cells.
During this or the next week of the second trimester of pregnancy, the sex of the fetus will be clearly visible (although in fact, the sex of the fetus is determined by genetic material, so as soon as insemination the fetal sex has been determined!).
At this point the fetus is about 87 mm long and weighs about 45 g.

3. 15th week: scalp has hair growth

In the 15th week of the 2nd trimester (equivalent to 13 weeks after fertilization), the fetus will develop very quickly. The bone continues to grow further, and will be visible on ultrasound after a while. The hairy part of the baby's scalp is also starting to form.

4. Week 16: eyes start to move

In the 16th week of pregnancy (equivalent to 14 weeks after fertilization), the fetal head hardens. Your baby's eyes may move slowly. The fetal ear also enters the final stages of completion.
Fetal limbs are able to move together and can be seen during ultrasound. However, these movements are too small for pregnant women to feel.
At this 16th week, the fetus is about 120 mm long and weighs about 110 g.

dau-hieu-thai-phat-trien-tot-3-thang-giua-1 — Tuần thứ 16 của thai kỳ (tương đương 14 tuần sau thụ tinh), đầu của thai nhi cứng lên

5. 17th week: toenails begin to grow

In the 17th week of pregnancy (equivalent to 15 weeks after fertilization), the toenails of the fetus begin to appear.
The fetus in the amniotic chamber moves more, begins to roll, rotate, and flip. The fetal heart can now pump about 100 pints of blood per day (~47 - 48 liters of blood per day)

6. Week 18: the fetus begins to have the ability to hear

During the 18th week of pregnancy (equivalent to 16 weeks after fertilization), the fetal ears begin to protrude, and the fetus begins to be able to hear. The baby's eyes start to look forward, and the digestive system also begins to work.
At the 18th week of pregnancy, the fetus is about 140 mm long and weighs about 200 g which are signs of good fetal development in the second 3 months

7. 19th week: the protective layer of the baby's skin develops

In the 19th week of pregnancy (equivalent to 17 weeks after conception), fetal growth slows down.
A greasy, cheese-like layer appears, covering the fetal skin called the vernix caseosa. The layer of caustic substances works to protect the sensitive skin of the fetus against friction, cracking or thickening due to contact with amniotic fluid.
With a female fetus, the uterus and vaginal cavity gradually form in the 2nd trimester

8. Week 20: a journey has passed

The 20th week of pregnancy (equivalent to 18 weeks after fertilization), is the halfway point of pregnancy. At this time, the pregnant woman can feel the movement of the fetus. The fetus will alternately sleep and wake, and of course, the fetus may be awakened by noise or movements of the pregnant woman.
At this time, the fetus is about 260 mm long and weighs about 320 g.

9. Week 21: the fetus can suck its thumb

The 21st week of pregnancy (equivalent to 19 weeks after fertilization) the whole body of the fetus is covered with a soft layer of hair. This layer of fluff plays the role of helping to keep the substance on the baby's skin.
Fetal sucking emission is also formed. The fetus begins to suck the thumb.

10. 22nd week: visible fetal hair

In the 22nd week of pregnancy (equivalent to 20 weeks after fertilization), the fetal hair and eyebrows are visible. A layer of brown fat also forms, which plays a role in retaining heat.
With a male fetus, the testicles begin to move downward.
At this time the fetus is about 280 mm long and weighs about 460 g.

11. Week 23: fingerprints and foot prints form

dau-hieu-thai-phat-trien-tot-3-thang-giua-2 — Tuần thứ 23 là khoảng thời gian quan trọng khi mang thai 3 tháng giữa

In the 23rd week of pregnancy (equivalent to 21 weeks after fertilization) the fetal eye starts to have rapid movements. Grooves also begin to appear in the hands and feet, which will later become an extremely important biometric factor, that is, fingerprints and foot prints.
This is an important period in the second trimester of pregnancy. The fetus may start hiccups, causing sudden jerky movements.

12. Week 24: Fetal skin has wrinkles

The 24th week of pregnancy (equivalent to 22 weeks after fertilization) the fetal skin appears wrinkles, is no longer transparent as before, and is pink or red (the color of blood in the capillaries).
At this point, the fetus is about 300 mm long and weighs about 630 g.

13. Week 25: The fetus responds to the mother's words

In the 25th week of pregnancy (equivalent to 23 weeks after fertilization), the fetus can move in response to familiar sounds such as the mother's voice.
The baby's sleep at this time is mostly rapid eye movement (REM) sleep (a phase of sleep, when the eyeballs move very quickly even though the eyes are still closed).

14. 26th week: fetal lungs develop

At 26 weeks of pregnancy (equivalent to 24 weeks after fertilization) the fetal lungs begin to produce surfactant, which is a substance that keeps the alveoli open when inhaled and does not collapse or stick when exhaled.
At this point the fetus is about 360 mm long and weighs about 760 g.

15. 27th week: end of the second trimester (second trimester)

dau-hieu-thai-phat-trien-tot-3-thang-giua-3 — Tuần thứ 27 của thai kỳ (tương đương 25 tuần sau thụ tinh) là cột mốc kết thúc mang thai ba tháng giữa

The 27th week of pregnancy (equivalent to 25 weeks after fertilization) marks the end of the second trimester of pregnancy. At this time, the nervous system of the fetus continues to mature. The baby's fat layer begins to appear, making the baby's skin look smoother and smoother.

To protect mother and baby during pregnancy, Vinmec provides a package Maternity service to help monitor the health status of mother and baby comprehensively, periodically check antenatal care with leading obstetricians and gynecologists. Perform all important tests and screenings for pregnant women, provide advice and timely intervention when detecting abnormalities in the health of mother and baby.
For detailed information about all-inclusive maternity packages, please contact the hospitals and clinics of the Vinmec health system nationwide.

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Articles refer to sources: mayoclinic.org and babycenter.com