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Are you currently creating a human? Or maybe you’re just curious about birthin’ babies. The miracle of childbirth may not feel like a miracle while you’re sweating like a beast and in the worst pain of your life. But despite the temporary agony, contractions serve an important purpose.

To put it simply: Contractions tell your baby it’s time for their grand debut. Your uterine muscles tighten, pushing the baby out of you and into the world.

Here are some common symptoms:

  • intense pelvic pressure
  • dull backaches
  • pain radiating from the back to the front of your pelvis
  • tensing and hardening of your belly

Here’s everything you need to know about contractions and some potential issues to look out for.

Contractions come in waves. The pain goes up, peaks, and goes down. This continues on a loop throughout labor.

Your contractions, which are brought on by a hormone called oxytocin, become more frequent and intense as you get closer to delivery. This pressure helps your cervix open (dilate), making it easier for the baby to pass through your vajayjay.

Contractions, or the sensation of contractions, can happen before you reach full-term. Here’s what to look out for.

Preterm contractions

Labor contractions shouldn’t hit until your bun has been in the oven for at least 37 weeks. If you feel consistent contractions earlier than that, you may be experiencing preterm labor.

It’s estimated that 9.5 percent of babies worldwide are born early, so preterm contractions aren’t uncommon. But preemies often have a higher risk of health issues than full-term babies. If you think something is going on, listen to your gut and call your doctor. If you can’t reach them, head to the hospital ASAP.

Braxton-Hicks

These are the fool’s gold of labor pains — the dress rehearsals for the big show. During Braxton-Hicks contractions, your stomach tightens and you may feel an uncomfortable amount of pressure in your lower abdomen.

This can be scary, especially if you’re expecting for the first time. The good news is that they usually aren’t too painful. But if you’re in pain and a man tries to tell you you’re overreacting, feel free to chant, “No uterus, no opinion!”

Braxton-Hicks contractions are most common during your third trimester, but they may make an appearance in your second. They tend to be sporadic, with no genuine pattern. They usually last from 30 seconds to 2 minutes and are most common after you’ve had an active day.

Fun fact: They were named after John Braxton Hicks, an English doctor who first described them in 1872. It’s a good thing his name wasn’t Banana Hammock or something like that. Actually, that would be pretty fantastic.

Back labor

When it comes to pregnancy, discomfort is just part of the deal. This often includes back pain. In addition to normal aches, you may also experience back labor. If you’re thinking, “What in the fresh hell is that?”, you aren’t alone.

Basically, if your baby is positioned a certain way, you may feel a less-than-pleasant sensation in your lower back. Women who have back pain while menstruating are more likely to have back labor. But it’s generally harmless, and the pain should subside immediately after birth.

Here’s the contraction situation for each stage of pregnancy:

Weeks 1–13first trimesterYou shouldn’t feel any contractions at this stage. If you do, call your doctor immediately.
Weeks 14–26second trimesterYou may start to feel Braxton-Hicks contractions. You may also experience round ligament pain.
Weeks 27–40third trimester This is when Braxton-Hicks contractions are most likely to occur.
Weeks 37–40nearing your due dateIt’s showtime! This is when real labor occurs.

When to ring the doctor

If your contractions start developing a pattern, you’re probably in labor. This is when you should call your doctor and/or midwife.

Some other signs of labor include:

Another labor indicator is the ripening (or thinning) of your cervix. This is when your cervix dilates to get ready for birth mode. You won’t be able to see how many centimeters you’re dilated — only a midwife, doctor, or trained doula can gauge that.

There’s no shame in calling your doctor, even if it turns out to be a false alarm. They’re there to help, and it’s always better to play it safe.

Now you know the symptoms of real labor and other possible contraction scenarios. But there are two other issues you need to look out for.

Round ligament pain

Round ligaments are a pair of ligaments that hold your uterus in its position. They lengthen throughout your pregnancy to make room for your growing baby.

Certain movements can stretch the ligaments too quickly, pulling on nerve fibers. Ouch. Round ligament pain generally happens in the second trimester. It might feel alarming but isn’t something to be too concerned about.

Indigestion

Pregnancy comes with all sorts of new sensations, including an excessive amount of gas, heartburn, and acid reflux. Indigestion can be caused by your baby pressing against your organs and/or by hormonal changes.

Symptoms include:

  • farting and burping
  • nausea
  • vomiting
  • heartburn
  • bloating

If typical antacids don’t help, talk to your doctor about other options. You can try switching up your diet to avoid foods that trigger a boisterous belly.

And don’t worry about letting it rip, ladies. You’re manufacturing a person inside you. You’re allowed to fart without shame.

Timing your contractions is super important. It will help you understand if you’re in labor and calculate how close you are to delivery. You’ll time from the moment one contraction starts until the next one begins.

Here’s how to do it:

  • When you feel a contraction coming on, start the clock.
  • Note when the pain peaks.
  • Once the pain subsides, mark how long the contraction lasted (but keep the timer running).
  • Wait until the next contraction starts to stop the clock.

Most doctors tell you to contact them when your contractions are 5 to 10 minutes apart. Depending on your pregnancy and previous births, they may ask you to call them sooner.

Labor stageTime between contractionsLength of contraction
early labor5 to 30 min30 to 45 sec
active labor3 to 5 min45 sec to 1 min
transition (final contractions before delivery)30 sec to 2 min1 to 1 1/2 min

Even before they’re born, babies have minds of their own. There’s no way to know for sure when your bébé will arrive, unless you have a scheduled delivery. Most babies are born between 37 weeks and 40 weeks. This is when you should be on full labor alert.

If you have contractions before the 37-week mark, you could be going into premature labor. This can be risky for you and your baby, so call your doctor immediately.

“The earliest ones feel like period cramps. The active labor contractions feel like a tightening and pressure that requires all of your focus and breath to move through. The strongest final ones feel like a force of nature moving through you! They are so powerful and intense, and the most amazing thing is that it is the power of your own body giving life. It can’t be stronger than you because it is you!” —Kiersten

“To be honest, it sort of felt like I had to take a massive poo. Like, really bad. But as it got closer to pushing time, the pain got way more intense but also kind of beautiful in a way. It’s hard to explain. I just felt super connected to my body and my baby. I really got in the zone.” —Maggie

“I spent my whole life dreading what labor would feel like, and in the end, I think I psyched myself up for nothing. Sure, it was painful, but it felt like super bad period cramps. And I already get really bad cramps, so maybe I was just used to it. The hardest part for me was just waiting around to meet my son.” —Samantha

If you’ve already had a baby, you know the drill. But each birth can be different from the last, and it’s important to stay on top of all possibilities. Come up with a birthing plan and have open communication with your doctor. If you think something is wrong, call them immediately.

And remember: Even though contractions suck, they’re absolutely worth the struggle. In the end, a beautiful, tiny little person is entering your life and the world. Congrats!