A membrane sweep is a procedure performed late in pregnancy to encourage labor. It involves a healthcare provider separating the amniotic sac’s membranes from the lower uterus. This stimulates natural labor processes without medication. Many consider this option to potentially avoid medical induction, especially near or past their due date.
Understanding the Procedure
A membrane sweep, also known as membrane stripping, is performed during a vaginal examination. The healthcare provider inserts a gloved finger through the cervix, if dilated, and sweeps it in a circular motion. This separates the amniotic sac from the lower uterus.
This physical separation releases prostaglandins, natural hormones that soften, thin, and dilate the cervix. These changes prepare the body for labor. The procedure is brief, lasting only a few minutes, and can often be done in an outpatient clinic setting.
Efficacy in Inducing Labor
A membrane sweep can increase the likelihood of spontaneous labor and may reduce the need for medical induction. Studies show individuals who undergo a sweep are more likely to experience spontaneous labor. For example, one study reported 90% of women who had a membrane sweep delivered by 41 weeks, compared to 75% who did not.
Success varies, with labor typically starting within 48 hours to seven days if effective. Factors influencing success include cervical readiness, often called a “favorable cervix.” While not guaranteed to initiate labor, the procedure can still help prepare the cervix by promoting ripening. A single sweep has been shown to reduce elective labor induction in postdate pregnancies.
Patient Experience and Considerations
During a membrane sweep, individuals may experience discomfort or mild pain, similar to a rough pelvic exam. Common after-effects include cramping, irregular contractions, and light vaginal bleeding or spotting. A “show,” a mucousy discharge possibly containing blood, can also occur. These symptoms are generally normal and do not harm the birthing person or baby.
While generally safe, rare risks exist. These include a small chance of accidentally rupturing the membranes (breaking the water) or infection. Healthcare providers typically offer a membrane sweep after 39 weeks, only if the cervix has begun to dilate. It is an optional procedure, and individuals can decline it.
Alternative Methods for Labor Induction
If a membrane sweep is unsuccessful or not an option, other labor induction methods are available. Medical techniques include prostaglandins, hormones administered orally or vaginally to ripen the cervix and stimulate contractions. Another common method is administering synthetic oxytocin (Pitocin) intravenously to cause uterine contractions.
A healthcare provider might also perform an amniotomy, intentionally rupturing the amniotic sac with a small hook-like instrument. This can increase cervical pressure and sometimes initiate labor. Mechanical methods, such as inserting a balloon catheter into the cervix, can also be used to help it dilate.