Heavy vaginal bleeding in the second or third trimesters of pregnancy usually involves a problem with the placenta. The two most common causes at this time are placental abruption and placenta previa. Preterm labor also can cause such bleeding.
Late bleeding may pose a threat to the health of the woman or the fetus. It may require treatment in a hospital or delivery.
The placenta is attached to the uterine wall. Placental abruption is when the placenta detaches from the wall before or during labor. This may cause vaginal bleeding. It often causes pain, even if bleeding is light or not seen.
When the placenta becomes detached, the fetus may get less oxygen. This can pose a danger.
Only 1% of pregnant women have this problem. It usually occurs in the last 12 weeks before birth. Those at high risk include women who:
- have already had children
- are older than 35 years
- have had abruption before
- have sickle cell anemia
Placental abruption has been linked to
- high blood pressure
- injuries to the abdomen
- cocaine use
Placental abruption is serious. It poses a risk to the woman and the fetus. Prompt care is needed.