Multiple Pregnancy

A multiple pregnancy occurs when a woman is carrying at least two fetuses at once. A multiple pregnancy results when more than one egg is fertilized and each egg implants itself in the uterus, or when one egg is fertilized and divides into two or more embryos, producing multiple "identical" babies. Most multiple pregnancies result in the birth of twins.

Nearly all multiple pregnancies are detected, using ultrasound technology, during the first trimester. A multiple pregnancy can pose a number of serious health risks and complications for both the mother and fetuses. One of the biggest concerns is premature birth, which increases the risk of birth defects, and future cognitive or medical issues. Because of the potential health issues associated with multiple pregnancy, it is always considered high risk, and requires proper prenatal care and close monitoring.

Causes of Multiple Pregnancy

A multiple pregnancy is linked to a variety of factors, including the following:

  • Family history of multiple pregnancy
  • Maternal age, especially being older than 35
  • In vitro fertilization (IVF)

In addition, ovulation- or fertility-stimulating medications, such as serophene or clomifene citrate, may produce multiple eggs at once.

Symptoms of Multiple Pregnancy

Although the specific symptoms of a multiple pregnancy vary by individual, many women experience the following:

  • Increased morning sickness
  • Noticeable fetal movement from different areas at the same time
  • Excessive weight gain, especially during the early stages of pregnancy
  • Increased appetite

In some cases, symptoms of a multiple pregnancy are similar to those of a single pregnancy, and the condition is not diagnosed until an ultrasound is performed.

Risks and Complications of Multiple Pregnancy

A multiple pregnancy is usually considered high risk because of its potential for causing health issues and complications. One of the most serious complications of multiple pregnancy is premature labor and delivery, resulting in an infant with low birthweight. The duration of a pregnancy usually decreases with the number of fetuses. Common risk factors that are associated with a multiple pregnancy include the following:

  • Gestational diabetes
  • Preeclampsia (pregnancy-induced hypertension)
  • Miscarriage or fetal loss
  • Underdeveloped lungs in the infants
  • Anemia
  • Abnormal discharge of amniotic fluid
  • Birth defects
  • Postpartum hemorrhage
  • Heavy blood loss
  • Urinary tract infection
If the health of the mother or fetuses is compromised before or during labor, a Cesarean delivery may be required.

Management of Multiple Pregnancy

Multiple pregnancy can be well managed through frequent prenatal visits to monitor health and check for complications. In addition, lifestyle changes, including better nutrition and increased rest, are often helpful. Generally, women who are carrying "multiples" are advised to gain between 35 and 45 pounds during pregnancy, which is approximately 10 pounds more than the recommendation for single pregnancies. Testing is required throughout pregnancy to monitor fetal health, and becomes more frequent if complications develop.

Premature labor is often a concern for multiple pregnancies. For women beginning to exhibit signs of premature labor, medications may be administered in order to stop or slow contractions. These medications can be taken orally or injected. Corticosteroid injections may also be necessary, if preterm labor occurs, to promote the maturing of the babies' lungs.

Delivery of Multiple Births

The approach to delivering multiples depends on the number of fetuses being carried, as well as the overall health of the mother. If the labor cannot be slowed or stopped, an emergency C-section may be required. If there are no complications, twins can often be delivered vaginally, but, when more than two babies are being delivered at the same time, a C-section is often necessary.

A multiple pregnancy can affect the babies' health in a variety of ways. One of the main concerns during a multiple pregnancy is preterm or premature delivery. Infants born prior to 32 weeks of gestation typically face more substantial risks than those carried closer to full term. Children of multiple pregnancies who have been born prematurely often suffer from low birthweight, and are at a higher risk for breathing problems, cerebral palsy, learning disabilities and developmental delays. In some cases, these conditions may be permanent; other types of health problems, however, may resolve as the child gets older. Multiples born prematurely typically must remain in a neonatal intensive care unit for some time.

Additional Resources