This is the first week of your second trimester of pregnancy. The baby grows slowly as all the internal organs have fully developed by this stage of pregnancy. The size of the fetus is small and there is sufficient space in the uterus for it to grow further. Morning sickness for most women will vanish at this stage and they will experience an increase in appetite.
The baby is around 2 1/2-3 inches long and weighs about 0.7 ounces. The baby’s head is still large when compared to the body, the eyes come closer and are fixed and the baby’s intestines also start moving into the body. The pancreas will start secreting insulin from this stage which is essential for regulating the sugar levels in life. The bones of the baby become harder. Tiny hair appears on the baby’s upper lip and eyebrows and it starts making creeping and climbing noises.
The placenta during the thirteenth week of pregnancy is fully functional and provides the baby with the essential oxygen, nutrients, minerals and fats. It also removes the carbon dioxide and waste materials by filtering it through the placental tissues. The placenta is bigger than the baby’s size and allows substances from the mother’s blood stream to pass on to the baby’s blood stream.
Some pregnancy symptoms around this stage include stretch marks in the hip, abdomen and buttocks region. Heartburn may also be experienced and you can take antacids on the advice of a health care professional. You should also avoid fried and oily items to avoid indigestion problems.
You might experience increased size of breasts which get prepared for lactation. Colostrum is produced in the breast milk at this stage. The baby is more flexible at the thirteenth week and moves its head from side to side.