When you’re in the final stages of pregnancy, contractions are like your body’s alarm clock, alerting you that you’re in labor. Sometimes, though, contractions can sound a false alarm.

These are called Braxton-Hicks contractions, named after the doctor who first described them. You can think of them as practice contractions that get your body ready for your baby’s arrival, but they are not the real thing.

Not sure whether you’re having Braxton-Hicks contractions or real ones? Here’s a guide to help you tell the difference.

Braxton-Hicks contractions are sometimes called “false labor” because they give you the false sensation that you are having real contractions.

Although they can thin the cervix (the opening of the uterus) as real contractions do, Braxton-Hicks contractions won’t ultimately lead to delivery.

Braxton-Hicks contractions typically start in your third trimester of pregnancy. They’ll arrive from time to time, often in the afternoon or evening and especially after you’ve had an active day. You won’t notice any real pattern, but Braxton-Hicks contractions may come more often the closer you get to your due date.

When a Braxton-Hicks contraction hits, you’ll feel a tightening in your abdomen. It’s not usually painful, but it can be.

Signs you’re having Braxton-Hicks contractions include:

  • contractions that come and go
  • contractions that don’t get stronger or closer together
  • contractions that go away when you change position or empty your bladder

Real contractions happen when your body releases a hormone called oxytocin, which stimulates your uterus to contract. They’re a signal that your body is in labor:

  • For many women, real contractions start at around the 40th week of pregnancy.
  • Real contractions that begin before the 37th week can be classified as premature labor.

Real contractions tighten the top part of your uterus to push your baby downward into the birth canal in preparation for delivery. They also thin your cervix to help your baby get through.

The feeling of a true contraction has been described as a wave. The pain starts low, rises until it peaks, and finally ebbs away. If you touch your abdomen, it feels hard during a contraction.

You can tell that you’re in true labor when the contractions are evenly spaced (for example, five minutes apart), and the time between them gets shorter and shorter (three minutes apart, then two minutes, then one). Real contractions also get more intense and painful over time.

There are other clues that you’re in labor, including these:

  • You may see a clump of pinkish or bloody mucus when you use the bathroom. This is called a “bloody show.”
  • You may feel like the baby has “dropped” lower in your belly.
  • You may experience fluid leaking from your vagina. This is a sign that your “water” (a bag of fluid called the amniotic sac) has broken.

This chart can help you tell whether you’re in real labor or just “practicing”:

Braxton-Hicks contractionsReal contractions
When do they start?As early as the second trimester, but more often in the third trimesterAfter your 37th week of pregnancy (if they come earlier, this can be a sign of preterm labor)
How often do they come?From time to time, in no regular patternAt regular intervals, getting closer and closer together in time
How long do they last? From less than 30 seconds to 2 minutesFrom 30 to 70 seconds
How do they feel?Like a tightening or squeezing, but not usually painfulLike a tightening or cramping that comes in waves, starting in the back and moving to the front, getting more intense and painful over time.

Contractions that only show up from time to time are most likely Braxton-Hicks. But if they start coming regularly, time them for about an hour. If they get stronger or closer together, you are likely experiencing true labor.

When they’re about five or six minutes apart, it’s probably time to grab your bag and head to the hospital.

If you’re not sure whether you’re really in labor, call your doctor or go to your delivery hospital. You’re better off seeking medical help, even if it turns out to be a false alarm.

It’s especially important to get to the hospital if you’re less than 37 weeks into your pregnancy, the contractions are especially painful, or your water has broken.