This is a condition where the placenta lies in the lower part of uterus. It can cause unexpected bleeding and can also interfere with the mode of delivery of the baby. Placenta Praevia occurs in 1 % of cases and is sometimes associated with abnormalities of uterus like fibroids, assisted conception or previous caesarean section. It may be diagnosed by a routine scan at 20 weeks when the placenta is seen to be lying over neck of womb.
Not all low lying placentas turn out to be Placenta Praevia. In 90 % of women the placenta will move upwards and out of way as the uterus gets bigger- these women can usually go on to have a safe vaginal delivery.
In some women, the first sign of Placenta Praevia may be dramatic but with painless bleeding after about18 weeks. The bleeding is normally bright red with no pain. Sometimes the bleeding can be recurrent and can be very worrying for the woman. She may need frequent visits to hospital to check that all is well. In many cases, the placenta will move upwards and bleeding should stop.
If the placenta remains over womb later in the pregnancy then delivery will always be by caesarean section. This is often done at 38 weeks, slightly earlier than normal, to avoid inevitable bleeding if you were to go into labour.
If the placenta remains over the neck of the womb, then the baby may lie in an odd position such as breech or transverse.
In the case of Placneta Praevia, is important to remember that the bleeding is not coming from baby so it will not affect his or her growth or development.