Trimester wise Fetal Development

Your pregnancy period which goes for nine months is divided into three equal parts which are called trimesters.

First Trimester of Pregnancy

During the second month of your pregnancy, your baby's backbone, brain, spinal column, nervous system, eyes, ears and nose start developing, and by the end of this term the baby's heart is well developed and begins to beat.

Then during the third month of your pregnancy, the foetus grows to three inches long and all the baby's organs begin to function. Then in the beginning of the third month, foetus is about three inches long and all the organs, muscles and nerves begin to function. You can also expect the wrists and ankles to have formed, and the fingers and toes to be clearly visible. Also, the eyelids cover the eyes and fingers and toes have soft nails; and the kidneys begin to secrete urine. Though the baby's genitals start to form, it is difficult to determine the baby's sex in the first trimester of pregnancy. Second Trimester of Pregnancy

We call the fourth month as the second trimester during which time your baby's cheekbones can be seen and its hair begins to appear. This is also that exciting time for a mother when the baby starts to kick and moves in the womb. The foetus develops taste buds and the baby may be beginning to savour the mother's meal.

Foetus's muscles start toning up in the fifth month and the lungs inhale and exhale amniotic fluid. Foetus is six inches long and can reveal his or her genitals. Sensory development starts taking place in the brain.

When this second trimester ends the foetus becomes eleven inches long and you can hear your sound. A protective creamy coating called vernix and downy hair covers the skin of the foetus. Third Trimester of Pregnancy

When the seventh month of pregnancy comes, the baby will start to sleep and awake at regular intervals, and the eyes will start to open and close. To accommodate the brain, his head starts growing bigger. Baby can differentiate between sounds and voices. Around this time the baby weighs about three pounds in this month.

The baby usually sleeps most of the time and moves frequently during the eight month. The coating on the skin begins to shed and all the organs and hair begins to grow. And then in the last month, when the baby becomes around 20 inches long it takes a 'head-down' position to exit from the birth canal.