Membrane Sweep: What It Is and What To Expect

As your due date approaches, you may find yourself daydreaming about ways to make the time go faster. Or maybe help your baby start their journey to the outside world sooner. About a week away from the big day, you may feel huge, uncomfortable, and past ready to meet your baby. At one of your last prenatal checkups, your provider might offer you a membrane sweep. But you might look back at them blankly and wonder, “What is a membrane sweep?”

Membrane sweeping, or membrane stripping, is a procedure that separates your baby’s amniotic sac from your uterus. Your baby’s amniotic sac surrounds them with fluid that cushions their body and lets them practice breathing, swallowing, and peeing. The amniotic sac pushes right up against the walls of your uterus, stretching and growing together as the baby develops.⁶

When your body notices the uterus and amniotic sac starting to part ways, it can release prostaglandins. These chemicals soften your cervix and can cause contractions. If the timing is right, these effects can jump-start your labor.²

Your healthcare provider can sweep your membranes in an exam room during a prenatal checkup, and it can sometimes get your labor started faster.^1,2

You can get a membrane sweep after the 38-week mark, but it’s common after 39 weeks. Remember, though, that your cervix must be partially dilated to get the sweep. However, this is unnecessary for successful labor, so there’s no pressure to do it.^2,3,7

Your doctor or midwife should be the only person doing the procedure. These professionals are trained to use techniques to minimize the risk of breaking your amniotic sac, which could introduce germs to your baby.

You can have the procedure done when your provider checks your cervix for dilation. If they find your cervix a little open and thinner than normal, they may offer to sweep your membranes, or you can ask them. Here’s how it usually goes:⁷

• You’ll lie on an exam table and put your feet up in stirrups.
• Your provider will use a gloved hand to insert two fingers into your vagina.
• You may feel some pressure as they check your cervix for dilation.
• Your provider will gently push their finger or fingers past the cervical opening alongside the baby’s head and use a circular motion to separate the sac from the inside wall of your uterus.
• Your provider will remove their fingers, and you can sit up.

At that point, you can start crossing your fingers and toes that it works!

Some pregnant people barely notice a membrane sweep, and others must breathe through it and say it’s intense. It can depend on your pain tolerance, anatomy, and provider, but whatever your situation, the procedure is quick but uncomfortable. If you get too uncomfortable, inform your provider, and they can stop immediately.⁷

After the procedure, you might notice some light bleeding and cramping. The cramps will either progress into labor or fade away. If it doesn’t work at 38 weeks, your doctor may offer to do it again at the next prenatal visit.^2,5,7

Research suggests the procedure can induce labor and lower the need for other induction methods. Other studies say it’s more of a hit-or-miss situation, but it can be more effective if your cervix is softened and dilated, you’re over 40 weeks pregnant, or you are already in early labor.^1,4,7

Risks and Benefits

The risks and benefits of membrane sweeping are still being studied, but one large study found that no one who had their membranes swept experienced any harmful effects.¹

You may feel ready to run to your OBGYN to ask for a membrane sweep, but keep in mind that there are some risks associated, like the following:³

• Irregular contractions
• Pain
• Vaginal bleeding

Some pregnant people hesitate to try it, and others may say these risks are well worth the chance to meet their baby (and see their toes!) sooner.

If it works, membrane sweeping can help get that labor party started. Some studies suggest this procedure can decrease the need for chemical induction with Pitocin. Other research found that pregnant people who had their membranes swept were more likely to go into labor before 41 weeks.^1,3

If you have questions or worries about membrane sweeping, you can ask away at your next prenatal visit. Whatever you choose to do, that baby is coming. If a membrane sweep works for you, great. If not, don’t worry because you’ll be holding your new baby soon without it.

Sources

1. https://www.aafp.org/afp/202/0700/

2. https://www.acog.org/

3. https://www.aafp.org/2014/0801/p160.html#sec-4

4. https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD000451.pub3/full

5. https://www.nhs.uk/

6. https://www.marchofdimes.org/

7. https://my.clevelandclinic.org/h21900