Signs you’re having twins or multiples

Early signs of a twin pregnancy include severe morning sickness, quick weight gain, and more breast tenderness. 

newborn twin babies making faces while lying on a green surface
Photo credit: Thinkstock

Are there early signs of twins?

You won't know for sure if you're carrying twins until you have an ultrasound, but there may be a few early signs. Some telltale early signs that you may be carrying twins include more severe morning sickness, extreme breast tenderness, or gaining weight more quickly.

Extreme fatigue might be a sign that you're carrying twins, but being super tired during pregnancy can also be caused by things like a normal singleton pregnancy, stress, a hectic work life, and a lot of responsibilities. Although it's possible, extreme fatigue early on doesn't necessarily mean that you're definitely carrying twins.

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The same goes for excessive morning sickness, which many women pregnant with multiples do experience but many do not.

Other early signs of a twin pregnancy can include a greater appetite (which includes that extra weight gain), "showing" earlier in pregnancy, and feeling the babies' movement in two different parts of the stomach.

If you feel that you're having above average morning sickness, early pregnancy exhaustion, lots of breast tenderness, and are gaining weight quicker than you expected, you may be pregnant with twins.


When will you find out you're having twins?

Typically, you'll find out if you're having twins during a first trimester ultrasound. An ultrasound will usually be able to detect a twin pregnancy early on, but sometimes a twin pregnancy can be detected even earlier through a pregnancy blood test.

If you have a multiples pregnancy then you might have higher levels of human chorionic gonadotropin (hCG), aka the "pregnancy hormone." But elevated hCG doesn't automatically mean that you're having twins either. You will still need to confirm your pregnancy status with an ultrasound.

The same goes for detecting twins with a Doppler, which detects fetal heartbeat sounds. A skilled doctor or midwife may be able to find two heartbeats but, because you may be able to hear a single heartbeat in two different areas of the mom's stomach, this is not the best way to tell if you are having twins. Instead, have your doctor do an ultrasound to find out.

The difference between fraternal and identical twins

Once you know you're having twins, you might be wondering what kind of twins you have: fraternal or identical. If you have identical twins, or monozygotic, it means that your twins share an amniotic sac and came from a single fertilized egg that divided into two. Meanwhile, fraternal twins, or dizygotic, came from 2 separate fertilized eggs that developed in 2 separate amniotic sacs.

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Your doctor will be able to tell in your ultrasound whether you have fraternal or identical twins, and can let you know. But the best way to determine if twins are identical or fraternal is through examining their DNA, since identical twins have the same DNA.

If you have fraternal twins, then the sex of your twins might be 2 boys, 2 girls, or a boy and a girl since fraternal twins are fertilized with 2 different sperm in 2 different eggs. Meanwhile, identical twins will always be the same sex at birth since they came from 1 sperm and 1 egg.

When you think of twins, you might be imagining two babies that look exactly the same - but that's not always the case. Since fraternal twins come from 2 different fertilized eggs, they can look very different from one another.

Depending on the type of twins, sometimes your doctor is able to tell if they are identical. However, in most instances, it 's not possible to tell for sure without a genetic test.

Learn more about twins:

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ACOG. Multiple Pregnancy. a new window [Accessed July 2021]

University of Rochester Medical Center. Symptoms and Diagnosis of Multiple Pregnancy. a new window [Accessed July 2021]

American Academy of Pediatrics. The Difference Between Identical and Fraternal Twins. a new window [Accessed July 2021]

Irina Gonzalez
Irina Gonzalez is an editor and freelance writer who covers parenting, recovery, and Latinx culture. In her spare time, she loves to explore her colorful home state of Colorado with her husband and spunky toddler.