Placenta Previa

Placenta Previa – the placenta presenting ahead of the baby – is one of the most worrisome diagnoses that an expectant mother can receive. The condition occurs fairly often and can present as anything from complete previa, where the cervix is entirely covered, to partial or marginal previa, where only the cervix is only partially covered.

The diagnosis is usually made as the result of an ultrasound in the second or third trimester, but symptoms such as painless bleeding during the later stages of pregnancy, early contractions, a baby in the breech position or an unusually enlarged uterus can all be indicators of placenta previa.

While this can be a frightening diagnosis, the good news is that the greater majority of cases will self-correct some time before delivery. In fact, almost all cases of complete previa and marginal previas will resolve on their own. Once placenta previa is diagnosed, further ultrasound testing will be required to carefully monitor the situation and the mother will usually be ordered to get complete bed rest, in the hospital if necessary. If there is concern about the condition preventing normal development of the baby, an early delivery may be necessary or the baby may be given intrauterine steroid shots to encourage maturity of the lungs.

Only in the rare cases when placenta previa persists until full term does it become a serious issue. Full term previa can cause life threatening blood loss to the baby and can result in stunted growth or other abnormalities. For the mother, there is a greater risk of needing a Cesarean, as well as extensive hemorrhage. The placenta may also attach directly to the uterine muscles, causing subsequent complications. If the condition extends into the last month of pregnancy, a Cesarean will be necessary to prevent hemorrhage.

While the causes of placenta previa are not known, there are some factors which do increase the risk for it. Older mothers and women who have had multiple pregnancies are usually at greater risk, as are women who have had uterine surgery.

Receiving a diagnosis of placenta previa can be scary, but as with all complications of pregnancy, the better your prenatal medical care the greater your chance of having a healthy delivery.