PLACENTA PREVIA

General Information

DEFINITION--A placenta attachment that is too low in the uterus and covers the cervix. This can be life-threatening to the unborn child. It occurs to some degree in 1 of 200 pregnancies.

BODY PARTS INVOLVED--Uterus; placenta (the organ that transfers nourishment and oxygen from mother to fetus); cervix (opening to the uterus).

SEX OR AGE MOST AFFECTED--Pregnant women.

> Sudden, painless bleeding during the second or third trimester of pregnancy--

especially the last 13 weeks. Bleeding may begin moderately and become severe.

• Abnormal fetal position in the uterus.

CAUSES--Normally, placenta attaches high on the uterus wall, away from the cervix. In placenta previa, the placenta covers the cervix partially or completely. Any change in the cervix, such as the softening and dilating that occurs close to delivery, can cause the placenta to bleed as it separates from the uterus.

RISK INCREASES WITH

• Fibroid tumors of the uterus.
• Diabetes mellitus.
• Previous uterine surgery.
• Smoking.
• Multiple previous pregnancies and deliveries.
• Mothers over age 35.
• Prior placenta previa.

HOW TO PREVENT

• Don't smoke during your pregnancy.
• Get good prenatal care during a pregnancy. It can't prevent previa, but can help prevent complications.

What To Expect

DIAGNOSTIC MEASURES--

• Your own observation of symptoms, especially of vaginal bleeding during pregnancy.
• Medical history and physical exam by a doctor.
• Laboratory blood tests to determine the amount of blood loss.
• Amniocentesis, and ultrasonography (See Glossary for both) to determine the exact location of the placenta.

APPROPRIATE HEALTH CARE

• Doctor's treatment.
• Hospitalization.
• Surgery to deliver the fetus by cesarean section (sometimes). Vaginal delivery is possible if the placenta separation is small or the cervix is covered only partially.

POSSIBLE COMPLICATIONS

• Premature delivery or fetal death, if extensive placenta previa develops before the expected delivery date.
• Hazardous blood loss, requiring blood transfusions for the mother.

PROBABLE OUTCOME--With prompt care, mothers and most infants survive without complications. In some cases, delivery is necessary before the fetus is mature enough to survive.

How To Treat

GENERAL MEASURES--

• Have regular checkups during pregnancy. If signs of placenta previa appear, be prepared to go to the hospital early for observation and possible delivery. Arrange for fast transportation to the hospital in case of emergency, especially massive bleeding.
• A marginal placenta previa requires bed rest in the hospital until bleeding stops. If bleeding stops, you may get up--but you should stay in the hospital until delivery. If you leave the hospital, your life and that of your child will be at risk. Massive bleeding can occur before you can get back to the hospital.
• If you are near the expected delivery date and studies reveal more than a marginal or low-lying placenta, immediate Cesarean section is necessary--even though the child is below optimal size and development.

MEDICATION--Only minimal analgesic medications--if any--will be used in delivery to increase the child's survival chances. Blood transfusions may be necessary. Don't use aspirin during pregnancy--it increases the risk of bleeding.

ACTIVITY--Rest in bed until bleeding stops or you deliver your child.

DIET--While you are bleeding and as long as surgery is being considered, drink liquids only. Eating solid food before surgery can cause anesthesia problems.

Call Your Doctor If

You have symptoms of placenta previa. Report any bleeding immediately. This is an emergency!