Amniotomy: When and Why Your Doctor Might Break Your Water

In some pregnancies, though, the amniotic sac doesn’t rupture on schedule, which can delay the onset of your labor. If this happens, your doctor may recommend an amniotomy: artificially breaking your amniotic sac.

While that word sounds a bit scary, the process of opening the amniotic sac isn’t anything to be afraid of. Read on to learn when an amniotomy might be necessary and what you can expect if you choose one to jumpstart your labor.

Again, during an amniotomy, a procedure that’s also known as an artificial rupture of membranes (AROM or ARM), your doctor intentionally breaks your water by puncturing the amniotic sac to stimulate or speed up labor.

The goal is to trigger contractions and cervical dilation via a hormonal response to the sudden release of amniotic fluid. 1

Why your doctor might recommend an amniotomy

Most of the time, the point of an amniotomy is to induce labor (and potentially to shorten its duration). 2 This can be necessary if your baby has been due for a while and just isn’t coming (a late-term pregnancy), or if you have a medical condition that makes remaining pregnant risky for you or the baby, such as preeclampsia. In that case, it makes sense to speed things along.

If your labor has already started but stalled out for some reason, an amniotomy can also be useful to intensify your contractions and get things moving again.

Beyond that, artificially breaking your water can be medically useful in a few other ways. It can help doctors with:

• Internal fetal monitoring: Releasing the amniotic fluid allows your doctor to more precisely track your baby’s heart rate via his scalp, which is good in high-risk situations (i.e., when you have a last-minute pregnancy complication).
• Facilitating assisted delivery: AROM makes the birthing process easier for difficult deliveries that require forceps or vacuum assistance.

Fortunately, getting an amniotomy is typically quick and won’t put your pain threshold to the test. Here’s what you can expect:

• Cervical check: Your doctor will first check your cervix to see how dilated you are and confirm that your baby is head-down, low in your pelvis, and pressing against your cervix.
• Amnihook insertion: The thin plastic amnihook used for this procedure looks a bit like a crochet hook. If you feel any pain from it at all, it’ll be brief.
• Membrane rupture: With a swift, gentle motion, your doctor will make a small tear in the amniotic sac and release the fluid.
• Fluid release: You’ll feel a gush or trickle of warm fluid, which your medical team will soak up with absorbent pads.

The process is even less painful if your doctor has already given you pain medication, like an epidural.

Overall, amniotomies are quite safe, and if you end up needing one, there’s no need to panic.

However, few (if any) medical procedures are completely risk-free, and no description of an amniotomy would be complete without listing the potential complications. These include: 3

• Infection: Once your amniotic sac ruptures, the risk of infection increases for you and your baby, especially with a labor that lasts longer than 18 hours.
• Pain: One purpose of an amniotomy is to stimulate your labor contractions. (Oftentimes, the pain will become more intense than pre-AROM contractions.)
• Umbilical cord prolapse: This is a rare but serious complication where the umbilical cord slips down through the cervix ahead of your baby, potentially cutting off his oxygen supply. 4
• Umbilical cord compression: It’s also possible your umbilical cord will get flattened by internal pressure after the fluid release, which can threaten your baby’s oxygen flow during contractions. 5

As mentioned, to avoid these risks (especially umbilical cord prolapse), your doctor will steer clear of an amniotomy if your baby isn’t in a well-engaged, head-down position.

No mom-to-be features an amniotomy in her ideal birthing plan. However, in certain situations, artificially breaking your water might be the best option for both you and your baby.

Before you opt for the procedure, sit down with your doctor to go over the particulars of your situation, including your medical history, your baby’s position, and your labor progress.