Placenta Previa

Understanding the risks of placenta previa

Also simply called low lying placenta, placenta previa is a condition in which your placenta is too close to your cervix. If you have symptoms of this condition, your doctor will perform tests to determine how low your placenta is situated and devise a customized treatment plan to ensure the health and safety of your baby.

Placenta previa is classified according to how much the placenta is obstructing the cervix:

  • In marginal placenta previa, the placenta is attached at the edge of the cervix.
  • In partial placenta previa, the placenta partly covers the cervix.
  • In complete placenta previa, the placenta completely covers the cervix.
 

In most cases, a low lying placenta is not a problem, particularly early in pregnancy. Very often, as your pregnancy progresses, the placenta will move farther away from the cervix and the problem will resolve itself. However, if you have partial or complete placenta previa later in pregnancy, you may be at risk for serious complications. Complete placenta previa also makes vaginal delivery impossible, so your doctor will schedule you for a cesarean section delivery.

Symptoms of Placenta Previa

The main symptom of placenta previa is painless bleeding from the vagina. Typically, this blood is a brighter than usual hue of red and first occurs in the late second trimester or early third trimester of pregnancy. Also, it is common for this bleeding to start, then stop for a period of several weeks before starting up again.

If you can feel pressure in your lower abdomen or have menstrual-like cramping along with painless vaginal bleeding, then you may have a low lying placenta. Some cases, though, are completely free of symptoms; your doctor will likely be able to diagnose the condition anyway, since the position of the placenta is visible in routine ultrasounds. Risk factors for placenta previa include scars in the uterine lining (for example, from a previous cesarean section), a large placenta (as with a multiple pregnancy) or an abnormally shaped uterus.

Treatment and Complications

Treatment typically takes a "wait and see" approach. No intervention may be necessary if the problem does not cause troublesome symptoms or complications. If you have a low lying placenta, your doctor will likely advise you to avoid strenuous activities, refrain from vaginal sexual intercourse after the 28th week of pregnancy, avoid the use of tampons and douches, and avoid pelvic examinations by doctors. In severe cases, your doctor may put you on bed rest.

Placenta previa and air travel can also cause some issues, so check with your doctor before boarding any flights. Your doctor may advise you not to travel at all during your third trimester, so that you are close to the hospital in case of an emergency.

The complications of placenta previa occur when there is heavy bleeding, or if your placenta is putting pressure on your cervix. When the cervix begins to open in preparation for labor, the placenta may detach and lead to maternal hemorrhage. This very serious condition can put both your life and that of your baby at risk. You may need a blood transfusion, or you may need to deliver your baby early, usually via emergency C-section. Aftercare may be necessary, as the complications can extend into your post-pregnancy life.