When Does Labor Start After Losing Your Mucus Plug?

Losing your mucus plug signals that labor may be approaching. Here’s what you need to know about why it happens, what to expect, and what you need to do next.

Pregnant Woman Looking at Stomach
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The words "mucus plug" may sound a little strange if you've never been pregnant before, but it's a natural and necessary stopgap your body makes before you give birth. When you are pregnant, your system generates a mass of mucus to block the cervix (or mouth of the uterus). This protects the uterine environment from infection and repels bacteria from the outside, says Kristin Mallon, a board-certified nurse midwife and chief strategy officer at Integrative Obstetrics in Jersey City, New Jersey.

This plug should stay in place throughout your pregnancy—but near the end of it, it will become more vulnerable. Small uterine contractions can start to open up the cervix, says Adeeti Gupta, M.D., an OB-GYN and the founder of Walk In GYN Care. The cervix also softens due to hormonal changes, leading it to open up further and release the mucus plug. This allows your baby to pass through more easily.

Some people will notice the loss of their mucus plug the moment it happens (it looks like a gelatinous blob of snot). It can be yellowish-white and tinged with red or brown streaks. You might see it while wiping yourself, find it in your underwear—or not notice at all. If you do see it, labor is on its way.

So how soon after losing your mucus plug does labor usually start? Here's what the experts say.

Does Losing the Mucus Plug Mean I'm Going Into Labor?

Yes, but not right that second. "The loss of the mucus plug, especially when there's a little bit of blood, is usually a good indicator that labor is coming within one to three days," explains Mallon. "But sometimes labor will come weeks after losing the mucus plug, so this guideline isn't 100% accurate." In other words, losing your mucus plug signals that labor is approaching, but it may take a while.

Your baby is still protected after the mucus plug falls out (unless your water has broken and you're in active labor). "Your cervix continues to produce mucus to replenish what is lost, and the amniotic fluid has many immunological agents that continue to protect baby against infection," says Clara Ward, M.D., a maternal-fetal medicine specialist in Houston.

What Should I Do After Losing My Mucus Plug?

If you notice it, you may be tempted to grab your hospital bag and run out the door. Don't. Just give your health care provider a call or (if it's 3 A.M.) report it to them the next day—even at your next appointment, says Mallon. For now, it's better to monitor your baby's movements.

"If contractions start, time them," says Dr. Gupta. "When they become regular—lasting at least 30 seconds and coming every three to five minutes—then you can go to the hospital." You should also head to the hospital if your amniotic sac ruptures (commonly known as your water breaking).

There is an exception to these rules. Anyone who's pregnant should visit their doctor ASAP if they lose their mucus plug before their 37th week. This isn't necessarily cause for concern, especially if it isn't your first pregnancy, but you should still have your provider rule out complications like preterm labor.

Keep Watch for Other Signs of Labor

After you lose your mucus plug, be on the lookout for additional indications that you are in labor. "Other signs include 'lightening,' or the sensation that the baby has 'dropped,'" says Dr. Ward. "While this may result in more pressure in the pelvic region, breathing may be easier."

Some people feel more cramping or back pain as their labor contractions start. You may feel less active and more fatigued, or experience a feeling of loose joints. Your health care provider can determine whether your cervix has started to dilate, and there may actually be telling lines on your buttocks.

Stay calm. "If you are full-term—more than 37 weeks—there is probably no need to call your doctor unless you are bleeding heavily, contracting regularly, the mucus is particularly foul-smelling, or you are concerned that you may have broken your water," says Dr. Ward. Still worried? Call anyway to be safe.

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