This period lasts 12 weeks.

By 4 months the placenta develops completely.

At this time the child's face is formed, muscle activity increases: at 13-14 weeks - a sucking reflex appears, and at 17 weeks the child can frown. The baby begins to move the limbs, and by the end of the 5th month the mother feels these "perturbations". At the age of 5 months the child can be pushed 20-60 times in half an hour. At week 20, the fetus can perform up to 200 movements per day.

During this period develops the nervous and endocrine systems. The pituitary gland, the epiphysis, the thyroid, the parathyroid, the pancreas and the sex glands, as well as the adrenal glands. The hepatic function begins to be performed by the spleen.

Approximately 16-20 hours a day the baby is sleeping. For the formation of neural connections and maturation of the central nervous system requires a phase of rapid sleep.

At the 6th month of pregnancy, the baby begins to perform respiratory movements, but air does not enter the lungs, as the lung tissue does not spread.

Esophagus, stomach, thick and small intestine, liver and pancreas by the 6th month already, as a rule, formed completely.

On the 5th month the vestibular apparatus begins to work in the child, by the 6th month the fetus can hear and see.

At the end of the 4th month the length of the fetus is 16 cm, weight - 120 g. The length of the fetus starting from the 5th month of pregnancy is equal to the number of months multiplied by 5 (5 months = 5x5 = 25 cm, 6 months = 6x5 = 30 cm). At the end of the 6th month, the length of the fetus is 30 cm, the weight is 600-680 g.

Health. Sumy. Ua.