A membrane sweep, also known as a stretch and sweep (or stripping the membranes), is a method used to try and start labour artificially.
It’s commonly suggested as a more ‘natural’ method of induction as it doesn’t involve any medication.
The idea behind a membrane sweep is to stimulate the production of prostaglandin, which is a hormone that prepares your cervix for labour. Your care provider inserts a finger through your cervix and firmly moves their finger around in a circular motion, separating the membranes of the amniotic sac from your cervix.
Often a membrane sweep is presented as a simple method to ‘gently’ encourage labor. It may even be recommended when there’s no medical indication for an induction, but simply because your estimated due date is approaching. While interventions have a place, even the most ‘natural’ sounding methods are still interventions with risks.
6 Facts You Need To Know About A Membrane Sweep
Here are 6 facts to know about membrane sweeps:
#1: A Membrane Sweep Isn’t Natural
Anything that attempts to kick start labour before it begins spontaneously isn’t natural. While often touted as an alternative to other methods of induction, a membrane sweep is still a mechanical form of trying to start labour ahead of time.
While induction can be necessary and a life saving intervention, there are many babies being born before they are ready due to non-medical reasons.
There are many risks involved with inducing labour and it should not be undertaken lightly.
#2: It May Lead To Further Interventions
If an induction is necessary for medical reasons, a membrane sweep can seem like a gentler option than medical methods of induction.
Yet we know as a matter of fact that many inductions are not being performed purely for medical reasons. There are increasing rates of induction for non-medical reasons such as convenience or post dates (baby has passed the estimated due date).
It can be tempting to try a membrane sweep to ‘get things going’ because it seems harmless compared to being induced with prostaglandin gel placed on your cervix or powerful synthetic oxytocin via a drip. But this is not necessarily the case. If a membrane sweep doesn’t bring on labour and your care provider doesn’t support waiting for labour to begin spontaneously, you are more likely to have a medical induction.
If your body and baby aren’t ready for labour to begin, then chances are you will have more interventions, such as forceps or vacuum assisted birth, or even a c-section. Your baby may also experience problems due to being born early, especially breathing problems.
No-one wants to be separated from their newly born baby longer than necessary, and if there are problems, it can be a while before you hold your baby — and you may not be the first to hold your baby either.
#3: It Can Be Painful
A membrane sweep can only be performed if your cervix is ‘favourable’. This means the cervix must be slightly open (usually 1-2 centimetres dilated) and softening. During late pregnancy, your cervix can be angled back toward your tailbone, making it difficult to reach. This posterior position of the cervix can make the sweep quite uncomfortable, or even painful.
If the cervix is closed but soft, your care provider can stretch or massage the cervix to stimulate it to begin to dilate. Stretching the cervix can feel very uncomfortable, and some women describe a sharp, shooting sort of pain.
After the membrane sweep, you may experience cramping and spotting or bleeding.
#4: Your Consent Is Required
Any procedure performed on you requires your informed consent. Some care providers routinely do membrane sweeps in the last weeks of pregnancy, in the belief this will reduce the length of pregnancy. You should be informed of this policy and your care provider needs to discuss with you the risks and benefits of membrane sweeping so you can make an informed choice whether to have the sweep or not.
Unfortunately, many women experience membranes sweeps during pre-natal appointments, and are not aware the procedure will be done until after it has occurred. This can be a very distressing and upsetting event.
#5: It Doesn’t Always Work
It’s a commonly held belief that approximately a quarter of women who have a membrane sweep will go into labour within 48 hours of the procedure. Studies on outcomes for membrane sweeps differ, but this independent Cochrane review of 22 trials showed sweeping the membranes didn’t produce clinically important benefits.
Most care providers will suggest another membrane sweep within 48 hours if the first sweep hasn’t kick started labour. This means repeat visits to your doctor’s office or hospital, as well as increasing the chances of more discomfort and possibly irritable uterus (when contractions begin but do not progress).
The stress of waiting and possibly dealing with ongoing unprogressive contractions can lead you to feeling very tired and over it – you may even decide to give up and accept more interventions to get it over with. The chances are most women will progress to having their waters artificially broken, followed by an artificial oxytocin drip. We also know a high percent of women who have artificial oxytocin also then seek an epidural, or other pain relief, risking further complications.
If your baby isn’t ready to be born, they simply may not be in a favourable position for labour.
This can impact the effectiveness of your contractions, causing labour to be slow and irregular. When labour is induced and doesn’t proceed in a certain pattern and timeframe, care providers are more likely to increase the pressure to speed things up. At this stage, you are likely committed to do whatever it takes to birth your baby, even if that means a c-section. It’s easy for a ‘simple’ membrane sweep to be the start of a cascade of interventions. Who would have thought?
#6: Increase Risk Of Infection And PROM
Anything inserted into the vagina has the potential to introduce bacteria, which can travel up to the cervix and beyond to the membranes. If bacteria makes its way through the cervix, there’s a chance that an infection may weaken the membranes, causing them to rupture prematurely (PROM). There’s also the chance your care provider can rupture the membranes while performing the sweep.
Once the membranes have ruptured, the seal protecting your baby from infection is no longer able to prevent bacteria reaching your baby. This increases the risks of further interventions, such as antibiotics and monitoring. If labour doesn’t begin spontaneously within 24 hours, you are likely to be scheduled for a medical induction.
If induction is necessary for medical reasons, a membrane sweep is not usually performed on its own – other methods are usually used. However, a sweep may be undertaken if your cervix is very favourable, in the hope of avoiding further interventions. The choice to have a membrane sweep should be made with full consideration of the risks and benefits for your personal situation, regardless of your care provider’s preference.