1. The development of fetal size in the third month of pregnancy. At the third month of pregnancy, the fetus has grown to about 5.4 centimeters long and weighs about 14 grams. At this time, the baby\’s head is larger than the body, and the fingers and toes have formed. In addition, the fetus\’s internal organs are also gradually maturing and developing. 2. Fetal movement at 3 months of pregnancy