Fetal Growth and Development During Pregnancy

Pregnancy is an overwhelming experience for all mothers. Many changes happen in mothers' bodies and the fetus inside their wombs. As it is an exciting phase, they want to keep track of fetal growth and development right from conception to its birth.

What is Fetal Growth in Pregnancy?

The fetus goes through numerous changes in these nine months of pregnancy. Starting from the time of conception till it's ready to survive in the outside world, it grows over a period of 40 weeks divided into three trimesters. The released egg after fertilisation converts into a zygote and then to a blastocyst, that implants into the uterus to rapidly form an embryo. Then this embryo grows faster and forms all the major organs converting into a fetus. Then the organs grow and develop completely to form a baby, thus covering all the fetal growth stages.

What are the Stages of Fetal Growth?

The fetal development by week is observed by doctors but is divided into three stages, called trimesters. Each trimester covers the three months of pregnancy respectively. During these 9 months of pregnancy, the fetus achieves its growth and development milestones till its birth.

1. First Trimester

The first trimester mostly consists of the embryonic development stage. In the starting three months of pregnancy, rapid changes happen from conception to embryo formation. These embryo cells multiply to form fetus organs and body. The placenta is also developed during this stage which plays a vital role in the pregnancy as the carrier of nutrients, oxygen, and water to the baby.

Moreover, the major organs are developed during this stage, including the eyes, arms, legs, facial features, mouth, nasal passage, taste buds, hair follicles, etc. Though there may be slow fetal growth in the first trimester, it is still the most important pregnancy stage because the chances of miscarriage drastically reduce after this stage.

By the end of the third month, the fetus's organs and limbs are present, and it starts exploring slight movements like opening and closing the fist. But these organs continue to develop fully to get functional in the further stages of the pregnancy.

2. Second Trimester

This trimester offers the best experience of pregnancy as the discomfort symptoms of the first trimester are probably gone. Moreover, fetal movements can be experienced, and the gender of the baby can be known (if it is allowed at your location).

The fetus grows rapidly in this trimester, due to which the mother can feel the pressure on their lungs, bladder, stomach, and kidneys. The baby's hair starts growing, and its muscles and bones get stronger to move. By the 15th week, the baby's movements can be experienced by the mother. By the 18th–20th week, the baby can hear the mother's voice and heartbeat.

The baby's skin starts getting covered by fat, and all the essential organs have developed by the end of the second trimester. Also, the baby's taste buds and sensory organs are developed, thus helping the baby to taste and feel the touch.

3. Third Trimester

It is the final stage of the pregnancy, and an important one as the fetus gains weight quickly at this stage to prepare itself for birth. The movements become regular, and the baby can now recognise the changes in the sound. All the baby's organs have fully developed, and it starts practising breathing and gets hiccups. In the last month, the fetus can blink, or close its eyes, turn its head, respond to sounds, touch and light, and can also grasp firmly.

In the last weeks of this trimester, it starts preparing itself for birth by changing its position, and the movement becomes less due to the lack of space in the womb. The lungs are the last organ to fully mature near the full term. The baby constantly keeps growing and gains weight until its birth. Once the labour and contractions start, the fetus moves towards the cervix, thus entering into this world as a baby.

Thus, pregnancy is a wonderful time for the mother and the baby to grow. That is why a mother needs to get plenty of rest, eat a balanced diet, and avoid stress, as these factors help achieve normal fetal growth.

What Causes Poor Fetal Growth?

The fetus should grow properly in the womb so all organs and tissues are fully formed before birth. In case the growth is smaller than the expected number of weeks of the pregnancy, it is called fetal growth restriction. Many factors related to the mother or the baby can lead to slow or poor fetal growth, such as

• Preeclampsia
• Multiple pregnancies
• Infection
• Poor lifestyle
• Low levels of amniotic fluid
• Placental insufficiency
• Chromosomal abnormalities
• Alcohol or drug use
• Umbilical cord abnormalities
• Underweight or obese

What Increases Fetal Growth?

Every mother desires to give birth to a healthy baby, thus follow these tips:

• Healthy and balanced diet
• Prenatal vitamins regularly
• Add nuts and dry fruits to the diet
• Keep yourself hydrated
• Stay calm, and avoid stress
• Adequate rest
• Proper medical guidance

Pregnancy is a pleasant journey, so the mother should take good care of the body and the fetus inside to give birth to a healthy baby. And don't forget to track fetal growth and development with regular doctor check-ups and ultrasound scans.

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