Tests and diagnosis

By Mayo Clinic Staff

Placenta previa is diagnosed through ultrasound, either during a routine prenatal appointment or after an episode of vaginal bleeding.

A definitive diagnosis may require a combination of abdominal ultrasound and transvaginal ultrasound, which is done through a wand-like device placed inside your vagina. Your health care provider will closely monitor the location of the transducer in your vagina to prevent any bleeding. In rare instances, magnetic resonance imaging (MRI) may be used to clearly determine the placental location.

If your health care provider suspects that you may have placenta previa, he or she will avoid routine vaginal exams to reduce the risk of heavy bleeding. You may need additional ultrasounds to determine the exact location of your placenta before delivery. Your baby's heartbeat may be tracked as well.

Jun. 02, 2011