PLACENTA PREVIA

 Basic information

description

• In placenta previa, the placenta is covering or near the cervical opening (called the os). The placenta normally attaches high on the uterus wall, away from the cervix. With placenta previa, it can block the cervical opening to the vagina (birth canal). Placenta previa carries a risk of excessive bleeding, which can threaten the wellbeing of the mother and the baby. A low-lying placenta diagnosed in early pregnancy usually self-corrects as the uterus enlarges. Types of placenta previa include:
  • Total placenta previa: The placenta completely covers the opening of the cervix. This type presents the most serious risk to the mother.
  • Partial placenta previa: The placenta partially covers the opening of the cervix.
  • Marginal placenta previa: The placenta just reaches the margin of the cervix.
  • Low-lying placenta previa: The placenta is near the cervix.

FREQUENT SIGNS & SYMPTOMS

• Sudden, painless bleeding during the second or third trimester of pregnancy. Bleeding may be mild at the start and become severe. Bleeding may not occur until after labor begins in some cases.
• Cramping may occur in some patients.

causes

The exact cause of placenta previa is unknown. There may be a number of factors involved.

risk increases with

• Previous uterine surgery involving the lining of the uterus. This includes dilation and curettage (D & C) and cesarean section.
• Smoking.
• Prior induced abortion.
• Multiple previous pregnancies and births.
• Pregnancy with twins or other multiples.
• Mothers over age 35.
• Previous placenta previa.

PREVENTIVE MEASURES

Placenta previa cannot be prevented. Good prenatal care during pregnancy can help identify it early.

expected outcomes

With prompt care, the outcome for mothers and term infants is good. Outcome for premature baby will depend on number of weeks of gestation and the baby's condition at birth.

possible complications

• Poor fetal growth, due to an abnormal placenta providing a decrease in blood flow and oxygen delivery
  • Premature delivery, or (possibly) fetal death.
  • Increased risk of clotting disorder (disseminated intravascular coagulopathy or DIC).
  • Rarely, blood loss could lead to maternal shock and death.

 diagnosis & treatment

general measures

• If bleeding occurs, medical tests may include blood studies and ultrasound to determine the exact location of the placenta. Rarely, a vaginal exam may be done.
• Treatment will depend on the type of previa, amount of bleeding, fetal age, condition and presentation, and the presence or absence of labor.
• Hospital care that includes blood transfusions, intravenous (IV) fluids, and oxygen may be needed with severe bleeding.
• If the bleeding is heavy or the pregnancy is at term, delivery is usually done. There may be a trial of labor for vaginal delivery or a cesarean delivery.
• If the pregnancy is between 34 and 37 weeks and the mother and fetus are stable, amniocentesis may be done to check fetal lung maturity. With mature lungs, the newborn will not need breathing support.
• If the baby's lungs are immature or the pregnancy is less than 34 weeks, the treatment may involve medical observation for a period. You may be placed on bed rest at home. Follow your obstetric provider's instructions carefully.

medications

• Steroids may be prescribed to help fetal lungs mature.
• Drugs to delay labor may be used in some cases.

activity

Rest in bed until bleeding stops or you deliver your child. Avoid sexual intercourse or douching

diet

No special diet.

 notify our office if

You or a family member has placenta previa symptoms. Report any bleeding immediately. This is an emergency!

Special Notes: