Incredibly exhausted, like in a next-level kind of way? Feeling extremely queasy every time you see or smell food? It may be your body just reacting to pregnancy — but it also may be a sign that you have more than one bun in the oven.

Although there’s been a slight decrease in twin pregnancies over the last several years, there were still 114,483 twin births in 2022, the latest year for which stats are available, according to the Centers for Disease Control and Prevention[1]

“This is due to reproductive technologies being more conservative with embryo transfers — not because the spontaneous twin rate is decreasing,” says Shannon Smith, M.D., a board-certified OB/GYN and partner at Brigham Faulkner OB/GYN Associates in Boston, Massachusetts, and a member of the What to Expect Medical Review Board.

Here are some things to know about twin pregnancies and twin pregnancy symptoms.

How soon can you tell you’re pregnant with twins? 

Your doctor won’t be able to tell for sure until your first trimester ultrasound, which is usually done between 6 weeks and 9 weeks of pregnancy but can be done any time before week 14.

It is thought that you might be able to tell that you’re having twins as early as 5 weeks if you have higher than normal human chorionic gonadotropin hormone (hCG) levels

Your body begins to make hCG as soon as the embryo implants in the uterus. Levels surge those first few weeks of pregnancy, and they usually double every two to three days for about 10 weeks.

If your doctor orders a blood test to check hCG levels and yours are sky-high, it may be a sign that you have two (or more!) babies on board.

Again, that’s not always the case, and you won’t know for sure until that first ultrasound. Keep in mind, though, that there’s sometimes a downside to knowing so soon.

Doctors can now identify twin pregnancies earlier than ever, but about 20 to 30% of the time, you end up losing a twin later in the first trimester — a phenomenon known as vanishing twin syndrome. When this happens, the tissue of the miscarried twin is usually reabsorbed by your body. 

Documentation of vanishing twin syndrome has grown significantly over the past few decades, as early ultrasounds have become routine. There are also more reports of vanishing twin syndrome in women older than 30, though that may be linked to the fact that moms over the age of 40 have higher rates of multiple pregnancies, especially with the use of fertility treatments.

The good news is that when vanishing twin syndrome occurs in the first trimester, a mom usually goes on to experience a normal pregnancy and delivers a single healthy baby with no complications.

How do doctors confirm twin pregnancies? 

Call it mother’s instinct, but you may have a sneaking suspicion that you’re carrying twins early in pregnancy. You won’t get a formal confirmation, however, until the doctor does an ultrasound in your first trimester.

This is usually done anytime before week 14 of pregnancy, although it may be done earlier, usually between weeks 6 and 9, if your doctor wants to date the pregnancy, or make sure the pregnancy is viable (this is usually more common when your pregnancy has involved fertility treatments). Your doctor may also order an earlier ultrasound if pregnancy bloodwork reveals the following: 

  • Elevated hCG levels. They may be quite high in a multiple pregnancy and your practitioner may want to confirm whether you're carrying more than one baby as soon as possible.
  • High Alpha-fetoprotein. This is a protein released by your babies’ liver and found in your blood. High levels can indicate that more than one fetus is making the protein.

Twin pregnancy symptoms

Double the babies sometimes means that you’ll have double the pregnancy discomforts — but not always. Each woman may have slightly different twin pregnancy symptoms. 

Some common signs of a twin pregnancy can include:[2]

  • More morning sickness. Nausea and vomiting can be worse in a twin pregnancy, thanks to higher levels of the hCG hormone circulating in your system. You may notice that it starts earlier, and lasts longer. And severe nausea and vomiting, a condition known as hyperemesis gravidarum, is more common among moms carrying twins too. 
  • Tummy troubles. Since there’s more crowding in the area, you can expect more strain on your GI tract. This can lead to common pregnancy digestive discomforts like heartburn, indigestion and constipation.  
  • Intense fatigue. No wonder you feel wiped out: Your body is working twice as hard to grow two babies. Since you’re probably also dragging around more weight, you’re also more likely to drag in general. Pregnancy symptoms like nausea or indigestion can also make it harder to sleep. And yes, if you’re expecting twins, you can also expect that it will thicken the normal brain fog of pregnancy. 
  • More weight gain earlier. Experts advise a normal-weight mom expecting twins to gain between 37 and 54 pounds. That means you’ll be gaining about a pound a week in the first trimester alone.
  • Increased appetite. You’ll probably notice an increased appetite to help encourage that extra weight gain, although some women struggle with such bad morning sickness it’s hard for them to get the calories they need.
  • More fetal movement sometimes in different areas of your tummy at once. While most pregnant women feel at some point that they’re carrying an octopus (or a professional boxer), you’ve now got four arms and four legs to pack plenty of punches and kicks. And sometimes you'll feel the babies moving at the same time but in different parts of your belly. 

In addition, if you fit into any of the following categories, you’re more likely to be seeing double with fraternal twins (not identical) at your first ultrasound:

  • You’re over age 35. Thanks to higher levels of the reproductive hormone FSH, you’re more likely to release two eggs when you ovulate.

  • You’ve had fertility treatments. Any type of treatment that stimulates ovulation or implants more than one embryo raises your odds of fraternal twins.

  • You’re overweight or obese. If you have a BMI of over 30 when you conceive, you’re more likely to give birth to fraternal twins.

  • You’re Black. Fraternal twins are slightly more common among Black women and less common among Hispanics and Asians.

While there’s no magic crystal ball to tell you that you’re having twins, you can rely on a few key signs — and the knowledge that you’ll learn definitively whether you're carrying two babies by the end of your first trimester.


Frequently Asked Questions

Some twin pregnancies increase your pregnancy symptoms, leading to more severe nausea or fatigue, but the only way to know for sure that you're having twins is by having an ultrasound.

The signs of a twin pregnancy are different for everyone, but typically include heightened normal pregnancy symptoms. Common signs include more severe nausea, earlier weight gain, intense fatigue and increased appetite.

Yes. A twin pregnancy can often be detected in your first trimester by an ultrasound at 6 weeks or later. If your healthcare provider checks your hcG levels, a higher-than-normal level can be a sign of a twin pregnancy. But you'll need an ultrasound to confirm that it's really twins.