A membrane sweep, also called membrane stripping or cervical sweep, is a common procedure offered in late pregnancy to encourage the onset of labor. It involves a healthcare provider manually separating the amniotic sac from the lower part of the uterus. This simple, non-pharmacological method aims to stimulate natural labor without medical induction and is an optional procedure.
Understanding the Procedure
A healthcare provider performs a membrane sweep during a prenatal appointment. The individual lies on an exam table, similar to a pelvic exam, with feet placed in stirrups.
The provider first conducts an internal examination to assess the cervix, checking if it has begun to dilate and soften. If the cervix is not sufficiently dilated or is firm, a membrane sweep may not be possible. If the cervix is receptive, the provider inserts one or two gloved fingers into the cervix and performs a circular sweeping motion around the top of the opening. This physical separation is thought to trigger the body’s natural release of prostaglandins, hormones that help soften, thin, and dilate the cervix, preparing it for labor. The entire process usually takes only a few minutes.
Reasons for a Membrane Sweep
Healthcare providers may suggest a membrane sweep when a pregnancy is at or near its due date, typically after 39 weeks of gestation. This procedure is often considered a first step to encourage labor to start naturally before other medical induction methods become necessary. It is an option to help avoid formal medical induction.
The procedure is an elective choice, and individuals can decide whether to proceed after discussing benefits and risks with their healthcare provider. It may be offered if the cervix has already started to dilate but contractions have not yet begun, or if contractions have started but are irregular or have stopped. A membrane sweep can also be offered to relieve the discomfort associated with being overdue.
What Happens After
Following a membrane sweep, mild cramping is a frequent occurrence, which some describe as similar to menstrual cramps. Light vaginal spotting or bleeding, which can appear reddish, pink, or brown, is also common and may be mixed with mucus, sometimes referred to as a “show”. These symptoms are normal responses to the procedure and usually resolve within 24 to 72 hours.
Irregular contractions may also begin after a sweep, but these do not necessarily mean that active labor has started. These contractions are often mild and may not follow a regular pattern. Individuals can take over-the-counter pain relief, such as paracetamol, and a warm bath to help manage any discomfort. It is advisable to contact a healthcare provider if there is heavy bleeding that soaks through a pad in an hour or is running down the leg, or if severe pain occurs.
How Effective is It and When is it Not Recommended
A membrane sweep can increase the likelihood of spontaneous labor, particularly within 48 hours to seven days following the procedure. While it is not guaranteed to induce labor for everyone, studies suggest it may reduce the need for further medical induction. For example, some research indicates that around 70% of low-risk individuals who undergo a membrane sweep may experience spontaneous labor. One study reported that 90% of women who had a membrane sweep delivered by 41 weeks, compared to 75% of those who did not.
Despite its potential benefits, a membrane sweep is not suitable for everyone. Healthcare providers typically do not recommend it if there are pregnancy complications or conditions. These include a low-lying placenta (placenta previa), a history of a prior cesarean delivery, or if the baby is not in a head-down position. The procedure is also generally avoided if the membranes have already ruptured (water has broken), if there is a current bacterial cervical infection, or active genital herpes. These precautions help ensure the safety of both the pregnant individual and the baby.