What Happens to the Placenta during Pregnancy?

The placenta is an important part of the life-support system for a developing fetus. This structure sends nutrients and oxygen from the mother's body to the fetus. The placenta also produces important hormones which help to protect the growing baby from infection. In some cases, the placenta is not formed properly during pregnancy, leading to potential complications for both mother and baby. Some of the most common problems affecting the placenta during pregnancy include placental abruption, placenta previa, and placenta accreta.

Problems with the placenta during pregnancy are relatively rare, although any concerns should be discussed with a doctor right away. In most cases, the placenta works properly and delivers all of the necessary oxygen and nutrients to the baby. A healthy placenta also helps to remove waste materials from the fetus which are then disposed of by the mother's body.

Placental abruption is a possible complication affecting the placenta during pregnancy. This is a medical condition in which the placenta begins to peel from the wall of the uterus before the baby is born. Placental abruption may be mild and cause few medical problems or severe enough to cause internal bleeding in the mother's body or keep essential nutrients or oxygen from getting to the baby. Symptoms may include vaginal bleeding, sudden abdominal pain, or tenderness in the uterine region of the body. In many cases, the baby will have to be delivered early in order to prevent severe complications such as fetal death.

Placenta previa is a disorder which can cause problems for the placenta during pregnancy. When this condition is present, the placenta lies lower than normal, either partially or completely covering the cervix. The delicate blood vessels which attach the placenta to the uterus may tear, causing vaginal bleeding and increasing the risks of a premature birth. Many women with this condition are admitted to the hospital for monitoring, and if the bleeding is severe, blood transfusions may become necessary. Doctors try to extend the pregnancy as much as possible, although premature delivery is often necessary.

Placenta accreta is yet another potential cause of problems with the placenta during pregnancy. This condition develops when the placenta is implanted too firmly and too deeply into the uterine wall. This is most likely to occur when there is scar tissue present from an abdominal surgery such as a previous C-section delivery. Placenta accreta prevents the placenta from completely separating from the uterus after delivery, increasing the chances of dangerously heavy bleeding. Treatment for this condition involves surgery to attempt to remove the placenta from the uterine wall, although a hysterectomy, or complete removal of the uterus itself, is often necessary.