"Placental abruption" means that the placenta has pulled away from the wall of the uterus. Placental abruption can happen in about 1 out of every 150 pregnancies, and some cases are more serious than others. Women who develop placental abruption are monitored closely during their pregnancy. The most common symptoms are vaginal bleeding, uterine pain, and uterine contractions.
In some cases, the bleeding stops on its own, and the placenta doesn't continue to separate from the wall of the uterus. If the abruption is not serious and the baby is able to develop to full-term, a vaginal delivery may be possible.
However, if the placenta continues to pull away from the wall of the uterus, the baby may become seriously deprived of oxygen. Abruption can also cause the mother and/or the baby to lose a serious amount of blood.
For this situation, a cesarean section may be considered safer and is usually recommended.