Twin Pregnancy

What is a twin pregnancy?

Twin pregnancies occur when there are two fetuses in your uterus at one time.

What are my chances of having twins?

The chances of conceiving twins, a type of multiple pregnancy, are low. Twins occur naturally in 1 out of every 250 pregnancies.

What are the signs of a twin pregnancy?

Certain circumstances are consistent with carrying more than one fetus. But experiencing the signs of a twin pregnancy doesn’t always mean you're carrying two fetuses.

These signs, some of which occur in the early weeks of pregnancy, include:

• Early fetal movement.
• Fetal movement in more than one area.
• Fundal height is greater than gestational age. The baby bump is measuring larger than expected.
• Gaining weight quickly.
• Having high levels of hCG, a pregnancy hormone, or alpha-fetoprotein (AFP), a protein made by the fetus’s liver.
• Hearing more than one heartbeat on a fetal Doppler.

What are twin pregnancy symptoms?

Twin pregnancy symptoms are similar to those of a single fetus (singleton) pregnancy but may be more intense.

You may experience:

• Breast tenderness.
• Fatigue.
• Frequent urination.
• Increased appetite.
• Morning sickness.

How is a twin pregnancy confirmed?

The most reliable method of confirming a twin pregnancy is prenatal ultrasound. This test uses sound waves to produce images of your uterus. Ultrasound makes it possible to see whether there are two fetuses.

How is a twin pregnancy belly different from a singleton belly?

With a twin pregnancy belly, your bump will show early on. You may need maternity clothes shortly after finding out you are pregnant. Your expanding bump may also cause you to outgrow clothes quickly because of extra weight gain. It’s common to put on around 50 lbs. during a twin pregnancy, compared to 30 lbs. for a singleton baby.

What are the different types of twins?

Twins are either fraternal or identical.

• Fraternal twins occur when two sperm fertilize two eggs in one cycle. This results in a separate placenta for each baby. Fraternal twin DNA is like that of siblings of different ages. They may be the same or of different sex.
• Identical twins happen when a single embryo from one egg and one sperm divide in two. The twins may share one or have separate placentas. Identical twins are always of the same sex.

Conjoined twins are extremely rare and occur when an identical twin embryo does not fully divide. The babies’ bodies are fused and may share vital organs. Common points of fusion are the chest or abdomen. This can result in a shared liver or heart.

How can I get pregnant with twins?

Circumstances that increase your chances of having twins include:

• Age: If you're over the age of 35, you're more likely to release multiple eggs during ovulation.
• Family history: If your mother’s side has a history of fraternal twins, there is a chance you could conceive twins naturally.
• Fertility treatments: Twin pregnancy is more common in those who have fertility treatments, such as in vitro fertilization (IVF).
• Having obesity: If you have a body mass index (BMI) higher than 30, you're more likely to conceive twins.
• Personal history: If you carried twins during a previous pregnancy, you’re more likely to conceive twins again.

How do fertility treatments raise the likelihood of twins?

Fertility treatments can lead to a twin pregnancy:

• When you take drugs causing you to release more than one egg per cycle.
• If you have IVF and have more than one embryo implanted.
• After IVF, if an implanted embryo splits in the early stages of pregnancy.

What is considered full-term for twins?

A full-term pregnancy is 37 weeks. Twin pregnancies rarely last this long, with the typical twin pregnancy lasting 35 to 36 weeks. It's common to go into labor sooner.

Few treatments are available to prevent preterm labor, and they're not always successful. Once you go into active labor, there's no way to stop labor from progressing.

How is prenatal care different with a twin pregnancy?

With twin pregnancies, both you and the twins face a higher risk of complications. Prenatal checkups occur more frequently with twin pregnancies, making it possible to detect issues in earlier stages.

Twin pregnancies are high risk because there are many potential complications. It's common to receive prenatal care from maternal-fetal medicine experts. These obstetricians specialize in preventing, detecting and caring for complications of high-risk pregnancies.

What types of complications are associated with twin pregnancies?

Twin pregnancy complications include:

• Anemia.
• Congenital conditions, including spina bifida.
• Gestational diabetes.
• High blood pressure during pregnancy (preeclampsia).
• Intrauterine growth restriction (IUGR).
• Low amniotic fluid (oligohydramnios).
• Placental abruption.
• Premature labor.
• Too much amniotic fluid (polyhydramnios).
• Twin-to-twin transfusion syndrome, in which only one twin receives adequate blood supply in the womb.

Premature twins are at risk for additional complications, which may include:

• Brain bleeds.
• Breathing issues from underdeveloped lungs, including apnea.
• Difficulty staying warm.
• Feeding issues.
• Low birth weight.
• Vision problems (retinopathy of prematurity).

How are twins delivered?

A cesarean birth (c-section) is likely with twin pregnancies. If you're pregnant with twins and not having complications, it's possible to try for a vaginal delivery.

A note from Cleveland Clinic

Finding out you're pregnant with twins can be exciting, but you might also feel overwhelmed. A twin pregnancy requires more frequent prenatal visits because there are higher chances of complications. And there's a good chance you'll deliver just before you're considered full-term. Though twins are often born via c-section, talk to your provider about the possibility of a vaginal delivery. They're there to help with any questions or concerns you may have.