What Physical Changes Happen in the Mother?
A mother's body begins to change as soon as the embryo attaches to the uterus. Throughout the nine months of a pregnancy, the mother's body changes a lot as the baby grows and develops.
First trimester
One of the first things that happens to the mother is that she begins to produce a hormone, made by the placenta, called Human Chorionic Gonadotropin (HCG). This hormone is critical for the healthy development of the embryo and fetus. It is also the hormone that most pregnancy tests check for to see if a female is pregnant.
Also during the first three months of pregnancy, most women's nipples begin to darken, and they generally have some tenderness and swelling in their breasts. Some mothers have nausea or changes in their appetites. These symptoms usually improve a little further into the pregnancy.
As pregnancy moves forward, the placenta, amniotic sac, and umbilical cord are formed. These nourish and protect the fetus.
Second trimester
During the second trimester, as the pregnancy progresses and the baby grows, the mother's uterus and abdomen grow and her hips begin to widen. Hormones begin to soften the vagina or "birth canal" to prepare it for childbirth, and changes occur in the mother's breasts to prepare them for milk production.
Third trimester
During the last trimester of pregnancy, the baby grows rapidly and the mother's uterus has to expand to accommodate it. Sometimes the mother gets stretch marks on her skin and experiences indigestion and heartburn. As the time for delivery gets closer, the mother can have an early form of milk called colostrum leak from her breasts.
Birth
Typically, the mother will give birth at the end of the third trimester. The mother's body and the developing baby have been preparing for birth. To learn more, visit What happens at birth?.
After delivery
During the weeks after the baby is born, the mother's uterus and stomach return to normal size and her skin coloring returns to normal. But some mothers are left with small, flat scars from the stretch marks.
When the mother's milk "comes in," her breasts may become engorged, large and sore. Some mothers even get a fever and chills for a few hours. The mother's nipple area may also be larger at this time. But mother's nipples don't stay sore, and soon breastfeeding becomes easier and more convenient. Breastfeeding is the healthiest option for babies and mothers. Babies who are breast fed are less likely to get illnesses caused by bacteria and viruses and less likely to be overweight as they develop. 78 Even if a mother decides not to breastfeed, her body will continue to produce milk for a period of time. For more information about breast feeding, visit this government Web site: http://www.4woman.gov/Breastfeeding/index.cfm?page=227
For more information, check out How does the baby develop?, or What happens at birth?.
Amniotic Sac: Fluid-filled sac that surrounds the fetus throughout pregnancy. Living in this fluid protects the fetus from injury and helps keep its temperature regulated.
Placenta: This flat organ, somewhat larger than a man's hand, attaches to the wall of the uterus. It is formed from tissue of both the mother and the fetus. The blood vessels of the fetus grow through the umbilical cord into the placenta. These blood vessels allow the fetus to trade nourishment and waste products with the mother's blood supply.
Umbilical Cord: Rope-like cord that connects the fetus to the placenta. The cord has a vein that carries oxygen and nutrients to the fetus. It also has two arteries that carry waste products away from the fetus.
Last revised: May 28, 2008
