Published on March 27, 2024

Water breaking: Understand this sign of labor

If you're pregnant, you might be curious about your water breaking — when it will happen, what it will feel like and what to do next. Recognize the signs of water breaking and know what it means for the timeline of your baby's delivery.

What will happen when your water breaks?

During pregnancy, your baby is surrounded and cushioned by a fluid-filled membranous sac called the amniotic sac. Typically, at the beginning of or during labor your membranes will rupture — also known as your water breaking.

If your water breaks before labor starts, it's called prelabor rupture of membranes (PROM). Previously it was known as premature rupture of membranes.

When your water breaks you might experience a sensation of wetness in your vagina or on your perineum, an intermittent or constant leaking of small amounts of watery fluid from your vagina, or a more obvious gush of clear or pale yellow fluid.

How can you be sure your water has broken?

It's not always easy to tell if your water has broken. For example, it might be difficult to tell the difference between amniotic fluid and urine — especially if you only experience a feeling of wetness or a trickle of fluid.

If you're uncertain whether your water has broken, call your health care provider or head to your delivery facility right away. Your doctor or a member of your health care team will give you a physical exam to determine if you're leaking amniotic fluid. In some cases, an ultrasound might be done to check your amniotic fluid volume. You and your baby will be evaluated to determine the next steps.

After your water breaks, when will labor begin?

Typically, after your water breaks at term, labor soon follows — if it hasn't already begun.

Sometimes, however, labor doesn't start. If you experience prelabor rupture of membranes, your doctor might stimulate uterine contractions before labor begins on its own (labor induction). The longer it takes for labor to start after your water breaks, the greater the risk of you or your baby developing an infection.

What happens if your water breaks too early?

If your water breaks before the 37th week of pregnancy, it's known as preterm prelabor rupture of membranes (preterm PROM). Risk factors for water breaking too early include:

  • A history of preterm prelabor rupture of membranes in a prior pregnancy
  • Inflammation of the fetal membranes (intra-amniotic infection)
  • Vaginal bleeding during the second and third trimesters
  • Smoking or using illicit drugs during pregnancy
  • Being underweight with poor nutrition
  • Short cervical length

Potential complications include maternal or fetal infection, placental abruption — when the placenta peels away from the inner wall of the uterus before delivery — and umbilical cord problems. The baby is also at risk of complications due to premature birth.

If you have preterm PROM and you're at least 34 weeks pregnant, delivery might be recommended to avoid an infection. However, if there are no signs of infection or fetal health problems, research suggests that pregnancy can safely be allowed to continue as long as it's carefully monitored.

If you're between 24 and 34 weeks pregnant, your health care provider will try to delay delivery until your baby is more developed. You'll be given antibiotics to prevent an infection and an injection of potent steroids (corticosteroids) to speed your baby's lung maturity. If you're less than 32 weeks pregnant and at risk of delivering in the next few days, you might be given magnesium sulfate to protect the baby's nervous system.

Corticosteroids might also be recommended starting at week 23 of pregnancy, if you're at risk of delivering within 7 days. In addition, corticosteroids might be recommended if you're between weeks 34 and 36 and 6 days of pregnancy, at risk of delivering within 7 days, and you haven't previously received them. You might be given a repeat course of corticosteroids if you're less than 34 weeks pregnant, at risk of delivering within 7 days and a prior course of corticosteroids was given to you more than 14 days previously.

If you're less than 24 weeks pregnant, your health care provider will explain the risks of having a very preterm baby and the risks and benefits of trying to delay labor.

What if your water doesn't break on its own?

During active labor, if your cervix is dilated and thinned and the baby's head is deep in your pelvis, your health care provider might use a technique known as an amniotomy to start labor contractions or make them stronger if they have already begun. During the amniotomy, a thin plastic hook is used to make a small opening in the amniotic sac and cause your water to break.

It's natural to feel anxious about labor and delivery. While you might not be able to predict when your water will break, you can take comfort in your knowledge about the next steps.