A condition when the placenta (afterbirth) is located either completely or partially covering the cervix. This condition occurs in approximately 1 in 300 pregnancies.

What causes placenta previa?

Risk factors include advancing maternal age (over 35 at time of delivery), mutli-parity, multi-fetal pregnancies and prior cesarean sections. The placenta may be located over the cervix in the first or early second trimester, however as the pregnancy progresses the placenta may appear to “move” away from overlying the cervix.

What are the symptoms of placenta previa?

Sudden bleeding from the vagina is the main symptom and can be severe and life threatening. This typically occurs near the end of the second trimester or beginning of the third. Cramps can also occur. Bleeding may stop on its own, but start again in a few days or weeks. Labor will sometimes start within a few days of heavy bleeding and sometimes bleeding will not occur until after contractions begin.

How is placenta previa diagnosed?

Placenta previa can be diagnosed with ultrasound and your doctor may want to confirm the location with a transvaginal ultrasound exam. If this isn't diagnosed beforehand, some patients may have painless vaginal bleeding as their first sign that something is wrong. If you are diagnosed with a previa and experience vaginal bleeding it's important to come to the hospital immediately for evaluation.

What is the treatment for placenta previa?

If the placenta remains over the cervix, then delivery by cesarean section is warranted. The timing would depend upon your clinical situation. You might also be prescribed medications that prevent labor and steroid shots that will help the baby's lungs mature in case of an early birth.