Placenta previa (placenta covers the cervix)

Abdomen | Obstetrics and Gynaecology | Placenta previa (placenta covers the cervix) (Disease)


Placenta praevia (placenta previa AE) is an obstetric complication in which the placenta is attached to the uterine wall close to or covering the cervix.

It can sometimes occur in the later part of the first trimester, but usually during the second or third. It is a leading cause of antepartum haemorrhage (vaginal bleeding). Because of the potential morbidity and mortality secondary to profuse bleeding, immediate gynecologic consultation should be obtained.

Causes and Risk factors

There are different forms of placenta previa: Marginal (the placenta is next to cervix but does not cover the opening); Partial (the placenta covers part of the cervical opening); Complete (the placenta covers all of the cervical opening)

Placenta previa occurs in 1 out of 200 pregnancies. It is more common in women who have: abnormally developed uterus, large or abnormal placenta, many previous pregnancies, multiple pregnancy (twins, triplets, etc. ), scarring on the lining of the uterus, due to surgery, c-section, previous pregnancy, or abortion.

Women who smoke or have their children at an older age may also have an increased risk.

Diagnosis and Treatment

Before gynecologic consultation or transfer, the hemodynamic stability of the patient should be addressed. This includes the establishment of 2 large-bore intravenous access lines with intravenous crystalloids or blood products, as necessary. Obtain continuous fetal monitoring, if available.

If the fetus is preterm and immediate delivery is unnecessary (eg, fetus < 37 weeks gestation and hemorrhage not present), the patient may be treated expectantly on an outpatient basis.

If the fetus is reasonably mature (ie, >37 weeks gestation) and the patient is in labor or if severe hemorrhage is present, therapy is directed at the delivery of the fetus. The patient should receive crystalloids and/or blood, and the patient should be transferred to the operating room with double set-up conditions.