What is placenta privea?

What is placenta privea and what does it mean for mother & the unborn child?

Placenta praevia is a condition where the placenta (afterbirth) implants close to the cervix (mouth of the womb) or over the cervix.

Early on in pregnancy this usually does not cause problems. As the womb starts readying itself for labour – the lower part of the womb starts forming. This usually occurs from 30 weeks gestation. A woman can then sometimes present with severe vaginal bleeding, because of the placenta separating from the womb. In a patient with a major grade placenta praevia (the placenta completely covers or partially covers the cervix) the bleeding can be severe or even life threatening. These patients are often admitted to hospital from 32 weeks so that they are close to a facility where they can receive a caesarean section and also possible intensive care treatment after the delivery. Patients with a major grade placenta praevia can not labour vaginally and have a 25% chance of needing a hysterectomy at the time of caesarean section to control bleeding.

Remember that the blood lost is usually only the mother’s, but that the fact that the placenta is separated from the uterus does put the baby at risk. The patient with placenta praevia will often receive a steroid injection to help mature the baby’s lungs as the baby is at risk of being delivered prematurely. Minor grade placenta praevia are slightly different in that some of these patients can labour normally and that these patients do not need to be hospitalised until they start bleeding. Placenta praevia also seems to be more common in patients who have had a previous caesarean section.

Answer provided by Dr Jean-Pierre du Buisson