This is the period between 13th to 24th week of pregnancy. Detailed below are the normal changes that take place in the growing baby during this stage.
At 13 wks: 7½ cms in length about 30 gms in weight. The uterus also grows in size and it is ONLY NOW that your obstetrician can feel it in the lower abdomen. The uterus measures about 10.2 centimeters and the amniotic sac contains about 100 ml of amniotic fluid. The growing baby is suspended in this fluid, protected it from injuries. The changes that take place during this period include:
Although all the organs are formed by the end of the thirteenth week, they are yet to mature and carry out their normal functions. At this stage of pregnancy, only a few disease causing agents such as those for syphilis, toxoplasmosis or certain viral infections can harm the baby and cause abnormal growth of a particular organ.
At 16 wks: 16 cms in length about 135 gms weight. Body changes during this period include:
During this period the baby continues to grow very rapidly and is about 251/2 cms and weighs about 340 gms. The muscles grow rapidly and therefore the limbs move actively. By this time a mother is able to feel the baby moving. The total volume of the amniotic fluid increases so that the baby is able to move and turn very easily.
At 24 wks the baby measures about 33 cms and weighs about 570 gms. During this period the baby continues to grow and the vital organs continue to mature. If the baby is born at this stage, it can survive for a short time. It cannot live longer as the lungs are not yet fully developed and mature. There are however reported cases of babies surviving at this stage after specialized care in the intensive premature baby care unit.