Placental abruption happens when there is bleeding behind the placenta, between the placenta and the wall of the uterus (womb). This may be just a small amount of bleeding. But if you have a large amount of bleeding, the placenta may partially or completely separate from the lining of your uterus before your baby is born.
Placental abruption can be a serious condition for you and your baby. A large amount of bleeding can be dangerous for you both and can deprive your baby of oxygen and nutrients.
Unfortunately, placental abruption increases the risk of your baby:
- Being born prematurely
- Having growth problems, if the abruption is small and goes unnoticed
- Being stillborn or dying in the first 28 days of life
Placental abruption is diagnosed in up to one in 50 pregnancies. It’s most likely to happen in late pregnancy, or when you’re in active labour.
No one knows exactly what causes placental abruption, but it has been linked with many other conditions, including if:
- You had placental abruption in a previous pregnancy.
- You have pre-eclampsia.
- You have bleeding in early pregnancy.
- You have a blood disorder which increases the likelihood of blood clots (thrombophilia).
- Your unborn baby isn’t growing as well as he should be (intrauterine growth restriction).
- Your waters break early.
- You have too much amniotic fluid (polyhydramnios).
- You have had a trauma or blow to your tummy, such as from a car accident or domestic violence.
In about 80 per cent of cases placental abruption causes some vaginal bleeding. This ranges from a small amount to an obvious and sudden gush. The blood may be fresh red blood or old blood that’s dark in colour.
Sometimes, though, the blood stays in the uterus behind the placenta. So you may not see any bleeding at all, but have pain in your back or belly. Some mums describe the pain of a small abruption as being like a bad bruise on an area of their bump. A large abruption will feel very painful, with your bump feeling tense and firm.
If you have any signs of a placental abruption, you need to go hospital for an examination. Call your doctor or the delivery suite of your hospital immediately if you have any of these symptoms:
- Vaginal bleeding or spotting
- If your waters break and the fluid is bloody
- Tenderness or pain in your belly
- Back pain
- Frequent contractions, or a contraction that doesn’t end
- Your baby isn’t moving as much as before
Call 999 if you’re losing a lot of blood and have signs of shock such as feeling weak, faint, pale, sweaty, disoriented or if your heart is pounding.