Can a Membrane Sweep Actually Induce Labor?

When you are nearing the end of your pregnancy, you might be ready for pregnancy to be over and to finally meet your baby. And if you are past your due date, your health care provider might talk to you about labor induction methods. If there isn't an immediate need to deliver your baby, they may suggest a membrane sweep to help things along. But what is a membrane sweep, and is it really effective at inducing labor?

Read on to learn what a membrane sweep is, how it is performed, what it feels like, who is a good candidate, and what to expect afterward.

What Is a Membrane Sweep?

A membrane sweep (sometimes referred to as "stripping the membranes") is a minimally invasive procedure where your health care provider separates your baby's amniotic sac from the lower part of your uterus with a gloved finger.

“A membrane sweep is similar to a cervical exam but with the goal of the provider placing their finger in the cervical os (inside the cervix) and separating the inferior pole of the membranes (the bag of water where your baby lives) from the lower uterine segment with a sweeping circular motion,” says James Miller, MD, an OB-GYN in Wooster, Ohio.

Typically, health care providers only offer membrane sweeps if your cervix has shown signs of dilation. If there is no dilation, your provider cannot perform the procedure. After the procedure, your body releases hormones called prostaglandins, which assist in softening your cervix and getting contractions started.

What Does a Membrane Sweep Actually Feel Like?

During a membrane sweep, you may experience:

• Cramping that feels like menstrual cramps
• Mild contractions for up to 24 hours afterward
• Slight spotting that lasts a couple of days

Chelsea Bagley, a mom of three from Central Texas, says when she was overdue with her last baby, she was hoping to avoid more medicalized inductions. So, she had two membrane sweeps, and the second was successful in inducing labor.

"After the first sweep, I had a few contractions within six hours of the procedure, but I didn't go into labor," Bagley says. "I was in active labor and had my baby within 12 hours the second time (a week later)."

As for what the membrane sweeps felt like, Bagley describes it as an extra-uncomfortable cervical check or Pap smear. "It is not a comfortable experience for the birthing person," Bagley admits. "I wouldn't say it's painful, but it's not a great feeling." If she were to rate it on a scale of 1 to 10, she says she would give it an 8 for general discomfort and a 4 for pain.

Either way, Bagley is glad she had it done. She believes her second membrane sweep was what brought her into active labor. "I'd recommend it if you're trying to avoid a medical induction," she offers.

Do Membrane Sweeps Work?

If you are strongly considering having a membrane sweep done, you may wonder how successful it will likely be. The good news is that it's often helpful, although it may take several tries. A Cochrane review found that compared to no intervention or "sham" intervention, people who had a membrane sweep were more likely to go into labor and less likely to have formal induction of labor.

"Membrane sweeping is an effective procedure, but it is dependent on the cervical exam before the procedure," says Monte Swarup, MD, FACOG, board-certified in OB-GYN and founder of HPD Rx. "The more favorable the cervix, the more effective." Dr. Swarup adds that membrane sweeps often must be done more than once—usually weekly during office visits—before they are effective.

Still, studies show that membrane sweeps can positively affect labor induction. For example, one study found that in people who were past their due dates, membrane sweeps were successful 86% of the time. Of those who went into labor, 86% required only one or two sweeps, and 14% required more than two.

Risks of Membrane Sweeps

Experts consider membrane sweeps low risk, especially compared to risks associated with other induction methods or risks associated with going past your due date. “All individuals that are safe to have a vaginal delivery can have a membrane sweep at 38 weeks or beyond,” says Dr. Miller.

But because there are some minor risks associated with a membrane sweep, you should never attempt it at home and only have it performed by your health care provider, warns Dr. Swarup. “They are safe, but there is a chance you will bleed or break your bag of water,” Dr. Swarup says.

Notably, there are also risks to prolonging pregnancy past your due date, especially once you hit 41 or 42 weeks pregnant. Although many people delivering post-term do well, they are more likely to experience complications, including:

• Meconium aspiration (when a fetus breathes in its first bowel movement in the womb)
• Neonatal acidaemia (when excess acid builds up in a baby's blood)
• Low Apgar scores
• Macrosomia (large fetal size)
• Neonatal death
• Severe perineal injury
• Postpartum hemorrhage
• Chorioamnionitis (amniotic fluid infection)
• Endomyometritis (uterine infection)

Like any intervention, it's important to weigh the risks and benefits.

What To Expect After a Membrane Sweep

It’s important to remember that most people don’t go into labor directly after a membrane sweep. “Labor is not definitive after a membrane sweep and could start at any time or not at all,” says Dr. Swarup.

Additionally, the membrane sweep may have to be done several times before it makes a difference. You and your health care provider will decide the right number of membrane sweeps and the best way to time them.

You can expect some light bleeding and cramping after a membrane sweep. That doesn’t mean that you are in labor, though, says Dr. Swarup. “The signs of labor are painful contractions that are consistent, at least every 10 minutes, and last at least one hour,” he notes.

Signs that may necessitate a call to your health care provider include:

• Bleeding
• Leaking water
• Decreased fetal movement

Otherwise, if everything seems normal after your membrane sweep, Dr. Swarup recommends contacting a health care provider as soon as you notice regular contractions.