Twin Pregnancy

What Is a Twin Pregnancy?

Twin pregnancies happen when two babies are growing in your uterus at the same time.

The chances of having twins are low. Twins occur naturally in about 1 out of every 300 pregnancies. An ultrasound is the best and most reliable way to confirm a twin pregnancy.

Having twins can make pregnancy and delivery a little more challenging. You have a higher chance of preterm birth and complications like preeclampsia. Your pregnancy care provider will monitor you and your twins closely. This extra prenatal care can help prevent complications and keep you healthy.

What are the different types of twins?

Twins are either fraternal or identical:

• Fraternal twins happen when two sperm fertilize two eggs. Each twin has its own placenta. Fraternal twins are like regular brothers or sisters — they’re just born at the same time. They may be the same sex or different sexes. This type of twin is more common.
• Identical twins happen when one egg and one sperm join and then split into two separate embryos. They may share a placenta or have separate ones. Identical twins are always the same sex.

Conjoined twins are another very rare type. They occur when an identical twin embryo doesn’t fully split.

What are the symptoms of having twins?

Twin pregnancy symptoms are like those of a single pregnancy, but may be more intense.

You may have:

• Breast tenderness
• Fatigue
• Needing to pee more
• Increased appetite
• Morning sickness

What are the signs of a twin pregnancy?

You may be shocked to find out you’re having twins because there are no signs. But sometimes, things happen that could suggest a twin pregnancy. These include:

• Hearing more than one heartbeat on a Doppler ultrasound
• Your belly measuring larger or ahead of schedule
• Gaining weight more quickly than usual
• Higher-than-expected levels of certain pregnancy hormones, like hCG or AFP (alpha-fetoprotein)
• Feeling movement in several places

Remember, only a pregnancy ultrasound can confirm you’re having twins.

How can I get pregnant with twins?

Getting pregnant with twins usually happens unexpectedly. But some factors increase your chances, including:

• Age: You’re more likely to release multiple eggs during ovulation if you’re over the age of 35.
• Family history: Your chances are higher if your mother’s side has a history of fraternal twins.
• Fertility treatments: Twin pregnancy is more common with fertility medication or with treatments like IVF.
• Body type: If you have a body mass index (BMI) higher than 30, you’re more likely to conceive twins.
• Previous pregnancies: You’re more likely to have twins if you’ve been pregnant before.

How is a twin pregnancy different?

With twin pregnancies, both you and the twins face a higher chance of complications. Prenatal checkups occur more frequently to detect these complications early.

Twin pregnancies are considered high risk. It’s common to receive prenatal care from maternal-fetal medicine experts. These doctors specialize in preventing, detecting and caring for complications of high-risk pregnancies.

Most twin pregnancies last 36 to 37 weeks. Single pregnancies often last until 39 to 40 weeks. Your provider may recommend an induction with a twin pregnancy. You’re also more likely to have a scheduled C-section if you’re expecting twins.

What are possible complications of twin pregnancies?

You’re at a higher risk for the following pregnancy complications when you’re having twins:

• Anemia
• Gestational diabetes
• Preeclampsia
• Problems with the placenta
• Intrauterine growth restriction (IUGR)
• Low amniotic fluid
• Too much amniotic fluid
• Twin-to-twin transfusion syndrome

Babies who are born preterm are at risk for complications, which may include:

• Low birth weight
• Breathing issues
• Difficulty staying warm
• Feeding issues
• Vision problems

Talk to your pregnancy care provider about what you can expect. They can help you understand the risks and how they plan to prevent complications. Rest assured, your provider will do everything they can to keep you and your twins safe.

What does a twin pregnancy belly look like?

With a twin pregnancy, your belly often shows earlier than it would with a single pregnancy. You may need maternity clothes sooner. Or you may find you need maternity clothes in a higher size. It’s common to gain about 50 pounds total with a twin pregnancy. You gain closer to 30 pounds with a single pregnancy. You may see this size difference in your abdominal area with a larger bump.