Low-lying placenta (placenta praevia)

If the placenta is lower than usual in the uterus (womb) at 20 weeks, you should be offered at least one scan later in pregnancy

The placenta is the organ that develops during pregnancy to support the baby. Normally, it is on the side of the uterus (womb). But sometimes it develops lower down (called placenta praevia). It may even cover the cervix, blocking the eventual route of the baby during delivery (called major placenta praevia). Women with a low-lying placenta have a higher risk of bleeding from the placenta in pregnancy or around the time of delivery

Most women who have a low-lying placenta on their 20-week ultrasound scan have no problems. At least one more scan will be recommended to check the position of the placenta in later weeks. If the placenta is covering the cervical opening or is very close to it when the baby's due dates gets close, a Caesarean section will be recommended as a vaginal delivery is not safe 

Sometimes in placenta praevia the placenta grows into the muscle layer of the uterus, and is known as placenta accreta. The placenta and uterus can’t separate at delivery, and there may be heavy bleeding – your doctor should talk to you about this if it's a risk for you

If you've been told you have a low-lying placenta

  • Have the scans recommended
  • If you have any vaginal bleeding, go to your nearest maternity unit straightaway
  • Because of the risk of bleeding with placenta praevia, your doctor may advise that you don’t have sex for the rest of the pregnancy, and that you eat foods with a high iron content; you may want to check about these issues if your doctor doesn't mention them
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