Your baby undertakes a fascinating journey from zygote to foetus to an infant. Even though you may not realise it, your baby starts developing from the first day of pregnancy. You will realise you are pregnant only after a month has elapsed. In the meantime, however, your baby has already begun its journey.
From the union of an egg and sperm comes a zygote which comprises 46 chromosomes (23 each from both you and your partner). These chromosomes determine your baby’s appearance, eye colour, intelligence, sex and many other characteristics. By the fourth week of your pregnancy, your baby develops into an embryo of cells and anchors itself to the wall of your uterus. In a few days, you realise that you are pregnant.
By the end of the first trimester (12 weeks) your baby develops the placenta, the beginnings of neural connections, a miniscule heart (you cannot hear it in the ultrasound till week 7) and there is the first development of internal organs in the body.
The baby’s growth during pregnancy really kicks into gear from the fourth month onwards. By now, his facial features have started to get more refined. In the previous month, his face has developed two dark dots for eyes and an aperture for a mouth. This month, his facial features get more developed, with the beginnings of tiny ear holes, a nose and the beginnings of eyelids. This month, your baby also develops sexual organs, the pancreas and bladder. At this stage, it is not possible to determine the sex of the child.
By the end of the second trimester, your baby develops arms and feet from their previous paddle-like appearance. Also, the foetus begins to breathe inside the amniotic fluid, which helps develop the lungs. Even the brain grows at a rapid pace by this time, with pronounced neural activity.
The third trimester shows your baby’s considerable growth during pregnancy. In this time, your baby develops muscle tone and his torso and legs also grow. With the reflexes growing, the baby starts to wriggle and kick inside the uterus – you can feel these stirrings right from the fifth month, but they get more pronounced now. In this time, your baby’s ears will fixate on the sides of his head, his eyes will have moved to the upper portion of his face, he will develop hair on his head and a fine down on his body, and his fingers and toes become well defined. His body growth becomes commensurate with the size of his head.
The third trimester is an exciting time for you and your baby. Since your baby can now hear even the minutest sounds, it is recommended that you sing to the baby, tell stories, or talk to it constantly. Your baby also kicks more and more as the pregnancy progresses to term. The child has grown considerably in size and weight, and you will feel his growth more in the last weeks. Finally, your baby will indicate the time to be born by pressing against your pelvis, eventually giving rise to birth contractions.