You are 40 weeks, or maybe even less than that, and your provider mentions a membrane sweep. But like WTF is that? What is a membrane sweep? Why do we do it? How effective is it? What are the risks? And what is the membrane sweeps place in the unmedicated and physiological birth? In this episode I cover all the membrane sweep basics plus the reason why you need to know your stance on the membrane sweep before your provider brings it up.
Listen to a podcast from Evidence Based Birth with more on the evidence of membrane sweeps: https://evidencebasedbirth.com/updated-evidence-on-the-pros-and-cons-of-membrane-sweeping/
Listen to the podcast series on cervical checks, episode 15, 16, 18, 20: https://www.lizziebolliger.com/directory
Learn more about Unmedicated Academy: fiercelizzie.com/unmedicatedacademy
Grab a spot in my free birth class, Take Back Your Birth, starting March 23: fiercelizzie.com/takebackyourbirth
Also called membrane stripping or a stretch and sweep.
Membrane sweeping is a mechanical method of labor induction, meaning it is drug-free method and involves mechanics, in this case the use of fingers to stretch and sweep the cervix. It involves the care provider inserting one or two fingers into the vagina and through the cervix, and then using a continuous, circular, sweeping motion to gently separate the amniotic sac from the cervix and lower part of the uterus.
Imagine you have an orange, you open the peel just a bit to fit a finger through. Then you insert your finger through the hole and between the orange/orange ‘membranes’ and the peel/skin of the orange and sweep your finger to separate the peel a bit more from the orange. This is really similar to a membrane sweep!
Membrane sweeping is performed to hopefully get labor going. It can increase your body’s natural release of hormones that contribute to cervical ripening or dilation, and promote uterine contractions. The stretching of the cervix during the sweep may also release oxytocin and prostaglandins- the two big hormones in labor.
So when providers are doing this, they’re hoping that they’ll help soften and ripen the cervix or kick start contractions to hopefully avoid a more formal medical induction of labor later on. Membrane sweeping is performed with consent during a cervical check and is done in office. This isn’t something you need to go to L&D for, and you’ll go home after. It can be done one time or many times during the last weeks of pregnancy.
In an updated Cochrane review by Finucane et al., published in 2020, they combined 44 randomized trials and 17 studies looked at the effects of membrane sweeping on labor starting spontaneously, and found on average you are more likely to have labor start on its own after a membrane sweep than not having a membrane sweep. And 16 studies reported on whether or not the patients needed to have an induction after a membrane sweep vs not. They found that women in the membrane sweep group were less likely to have an induction. However, this is not the best evidence quality, the evidence is low certainty. Check out the podcast linked in the show notes for a better explanation of how the evidence is low quality.
There is even less data on whether or not a membrane sweep can help ripen or soften or dilate the cervix. In one randomized trial, 165 participants with low Bishop’s scores were given a membrane sweep or not, and it was found that there was a significant increase in the average Bishop score 48 hours after- meaning the cervix was more ready for labor.
The sweep without consent is the biggest problem, some providers consider a sweep a routine part of cervical checks in the last weeks of pregnancy. It is very important that you tell your provider your stance on sweeps and cervical checks before they happen. I talk more about cervical checks in a series of episodes on the podcast, check out epsidoes 15, 16, 18, and 20 for more.
And the biggest downside of having a sweep done is the small risk of membranes breaking. If your waters break during a membrane sweep or cervical check, the womb is now opened up for infection and labor must start soon. In fact, it is likely your provider will want to induce your then and there without sending you home first (you can say no to this!).
Women also report that sometimes membrane sweeps can cause cramping and irregular contractions (not labor) that could interfere with your ability to rest and cause stress due to it being a false alarm of labor starting.
This is absolutely an intervention and not a part of physiological birth. However, it is unmedicated so it could be a good option for you if you are getting very close to 42 weeks and feeling pressured with a more formal medicated induction. Again, I want to remind you that you can always decline any intervention, a sweep or an induction, at any time if that is your preference!
If you liked this episode, this was a good preview of the kind of information you get inside of Unmedicated Academy. I think it’s really important to know your options, know the risks, know the evidence and also come at it from that unmedicated and physiological point of view. Your preferences for birth matter!
And also!! This is the kind of content you’ll be getting inside my next free birth class- Take Back Your Birth, a free 3 day event all about empowerment in your unmedicated hospital birth. Go to fiercelizzie.com/takebackyourbirth to grab a spot! We start on March 23! I’ll see you there!
Stay fierce moms!