to 40 percent during the first trimester. The breasts grow in size and become tender. The uterus just becomes palpable above the pubic bone at 12 weeks’ gestation. Women tend to be more energetic in the second trimester and the uterus can be seen above the pubic bone. In total, the uterus expands twenty times its normal size. Fetal movement is felt at about 20 weeks’ gestation or slightly earlier than that in subsequent pregnancies. In the third trimester, most of the weight is gained and the fetus sits in the head-down position most of the time. There will be regular fetal movement, which can be disruptive. Eventually, the head engages and there is increased pressure on the bladder. Prenatal care can begin before pregnancy with preconception counseling. Prenatal medical care is recommended throughout the pregnancy in order to monitor for pregnancy-related complications. Nutrition is important before and during pregnancy. Folic acid consumption is particularly important in order to prevent spina bifida in the fetus. Omega-3 fatty acids are also helpful in brain and eye development. Iron is important to prevent anemia. Calcium and vitamin D are important for bone development. Foods that should be avoided are those that are unwashed and might contain pathogens, and unpasteurized deli meats and dairy products. Women need to gain weight in order to have a healthy baby. Overweight women do not need to gain as much as underweight women. About 25 to 35 pounds is recommended for the woman who has a normal body mass index prior to getting pregnancy. Gaining too much weight can increase the risk of a cesarean section, hypertension in pregnancy, and large fetal size. Regular aerobic exercise is recommended unless there are pregnancy complications.
THE BIRTH PROCESS The birth process in humans is called childbirth. It is the final aspect of a pregnancy that involves expulsion of the fetus, which becomes an infant, from the vagina or through Cesarean section. Childbirth usually happens in a hospital in a developed country and in a home in developing countries.
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