A membrane sweep is a common procedure healthcare providers may suggest to encourage labor as a pregnancy nears or passes its due date. Expectant parents often wonder if this intervention can cause their “water to break,” a significant sign of labor progression.
Understanding the Membrane Sweep Procedure
A membrane sweep, also known as membrane stripping, is a procedure performed by a healthcare provider during a vaginal exam to encourage natural labor. The provider inserts one or two gloved fingers into the cervix and uses a circular motion to gently separate the amniotic sac from the lower part of the uterus. This separation helps to release prostaglandins, which are hormone-like substances that can soften, thin, and dilate the cervix, preparing the body for labor.
The procedure is typically offered after 39 weeks of pregnancy when the cervix has already begun to dilate. While it aims to stimulate labor naturally, there is no guarantee it will immediately start contractions. Individuals undergoing a membrane sweep may experience discomfort or pressure during the procedure, similar to a rough pelvic exam. Following the sweep, it is common to experience some cramping, irregular contractions, or light vaginal spotting.
The Likelihood of Water Breaking During a Membrane Sweep
While a membrane sweep is designed to separate the membranes from the uterine wall and release prostaglandins, not to rupture the amniotic sac, there is a small chance that the “water” can break during the procedure. This is a rare occurrence and is not the primary goal. The procedure specifically targets the separation of the chorionic membrane from the decidua in the lower uterine segment, which indirectly promotes cervical changes.
If the membranes are already very thin, bulging, or have a weak spot, the manipulation during the sweep could potentially lead to their rupture. One study indicated a 9% risk of water breaking in a group that received membrane sweeping compared to 0% in a control group, suggesting it is a potential, though not frequent, outcome. It is important to differentiate a true rupture of membranes from the light spotting or small amount of fluid that might occur due to irritation of the cervix during the procedure. Healthcare providers typically perform membrane sweeps only in full-term, healthy pregnancies.
Identifying and Responding to Water Breaking
Recognizing when your water has broken is important, whether it happens spontaneously or after a procedure like a membrane sweep. The rupture of membranes can manifest as either a sudden gush of fluid or a continuous slow trickle. Unlike urine, amniotic fluid is typically clear and odorless, or may have a slightly sweet smell, and it is usually thin and watery, differentiating it from thicker vaginal discharge. A key indicator is that the leaking fluid cannot be controlled or stopped, unlike urine.
If you suspect your water has broken, contact your healthcare provider immediately. They will advise you to note the time the fluid started leaking, its color, and the approximate amount. If the fluid is green, brown, or has a foul smell, it could indicate meconium (baby’s first stool) or an infection, requiring prompt medical attention.
Wearing a sanitary pad (not a tampon) can help assess the amount and characteristics of the fluid. Your provider may perform a test, such as a litmus or ferning test, to confirm if the fluid is indeed amniotic fluid. Following confirmation, your healthcare team will guide you on the next steps, which may include waiting for labor to progress or considering induction, as the risk of infection increases once the membranes have ruptured.