Having Twins

Today, twins are born once in about every 41 births. Having twins can bring great joy and rewards to a family. Sometimes, however, it also can pose a risk to the mother and her babies. Complications can occur that require special care.

How Twins Occur
When a sperm meets an egg in the fallopian tube, fertilization — union of egg and sperm — can occur. If this happens, the fertilized egg moves down the fallopian tube to the uterus where it attaches and grows into a fetus. During this process, twins can form.

Twins can be either fraternal or identical. Most are fraternal twins — each develops from a separate egg and sperm. Fraternal twins each have their own placenta and amniotic sac.

Identical twins are more rare. They occur when a fertilized egg splits early in pregnancy and develops into two fetuses. Identical twins may share a placenta, but each baby usually has its own amniotic sac.

Most twins are diagnosed before delivery. Your doctor may suspect that you are carrying twins if your uterus grows more quickly or is larger than expected. However, twins usually are diagnosed by using an ultrasound exam.

Prenatal Care
You will need special prenatal care with twins. You should see your doctor more often and you may need special tests.

When pregnant with twins, you will need to eat more than if you were carrying one baby. Eating well and gaining weight are important for your health and the health of your twins. Your body must nourish the babies and meet your energy needs as well. You will need to eat about 2,700 calories every day, if you are of average weight.

Twins can make you more uncomfortable than usual during pregnancy because the uterus becomes much larger. Resting during the day will help give you energy.

The risk of certain complications is higher in a twin pregnancy. The mother is more likely to develop high blood pressure or anemia, and the babies are more likely to be born small. The mother also is at increased risk for preterm labor.

Preterm Labor
Preterm labor is labor that starts before the end of 37 weeks of pregnancy. This can result in preterm birth, the most common problem of multiple pregnancy. About half of all twins are born preterm. When babies are preterm, they often have problems breathing and eating.
If you have preterm labor, you may be given injections of a steroid medication. This can help the babies’ lungs work better.

Preeclampsia is a condition of pregnancy in which there is high blood pressure and protein in the urine. Preeclampsia can be mild or severe.
This condition is harmful because it can reduce the blood flow through the vessels in the uterus. This may deprive the babies of oxygen and nutrients.

Growth Problems
Twins are more likely to be smaller than average. Ultrasound is often used to check the growth and the amount of amniotic fluid of each baby.

Twins are called discordant if one is much smaller than the other.

Fetal Loss
In some twin pregnancies, one of the babies dies. If this happens in early pregnancy, you may have some spotting or bleeding from your vagina. This does not harm you or the other baby.

Later in pregnancy, death of one of the babies is more serious, but often you can still have one healthy child.

Monitoring A Twin Pregnancy
Many techniques are used to check the well-being of your babies.

  1. Have you count your babies’ movements, called kick counts, at home
  2. Examine your cervix by physical exam or ultrasound exam for changes that may show early signs of preterm labor
  3. Repeat ultrasound exams to check the babies’ growth
  4. Measure the babies’ heart rate in response to their own movements (nonstress test)
  5. Perform a biophysical profile, which includes checking the babies’ heart rate, body movement, muscle tone, and the amount of amniotic fluid by ultrasound

In some cases, twins can be delivered by vaginal birth. In others, a cesarean birth, in which the baby is delivered through a cut made in your abdomen and uterus, may be needed.

Caring for Your Newborn Twins
Most twins do well at birth and can be cared for like any other healthy babies. However, caring for twins is stressful at times. Get as much rest as you can. You may feel overwhelmed, or even sad sometimes. If this occurs, let you doctor know.

Many women wonder if they can breastfeed more than one baby. The answer is yes. Mother’s milk is the best food for any infant. It has the right amount of all the nutrients the baby needs.

Having twins can be an exciting time. You can give your babies the best possible start by taking good care of yourself. Learn the warning signs of problems, and talk to your doctor or nurse about your questions and concerns.

This excerpt from ACOG’s Patient Education Pamphlet is provided for your information. It is not medical advice and should not be relied upon as a substitute for visiting your doctor. If you need medical care, have any questions, or wish to receive the full text of this Patient Education Pamphlet, please contact your obstetrician-gynecologist.

To ensure the information is current and accurate, ACOG titles are reviewed every 18 months

Copyright © November 2007 The American College of Obstetricians and Gynecologists