The placenta is the baby's lifeline. During pregnancy, the placenta connects the umbilical cord to the wall of the utuerus. It moves oxygen and nutrients from the mother to the baby. After birth, the placenta detaches from the uterine wall and comes out.

A huge amount of blood flows to the placenta to support the baby, and placental problems can cause dangerous amounts of bleeding.. The most common problems include:

  • placenta previa -The placenta attaches to the uterine wall close to the cervix, and causes bleeding as the cervix opens;
  • placenta accreta -The placenta attaches too firmly to the uterine wall and cannot detach easily after birth;
  • placental abruption -The placenta tears away from the uterine wall too early, causing bleeding and cutting off oxygen to the baby; and
  • retained placenta -The placenta stays in the uterus too long after delivery.