What are the pros and cons of a membrane sweep at 39 weeks of gestation?

From the Guidelines

A membrane sweep at 39 weeks is a reasonable option for women who want to avoid medical induction, but it should be considered carefully based on individual circumstances. This procedure involves a healthcare provider inserting a finger through the cervix and separating the amniotic sac from the uterine wall, which releases prostaglandins that may help initiate labor. The advantages of a membrane sweep include:

• Potentially reducing the need for formal induction methods
• Being a relatively simple procedure performed during a routine appointment
• Avoiding medications However, there are several drawbacks to consider, such as:
• Discomfort or pain during the procedure
• Spotting or irregular contractions afterward
• A small risk of accidentally breaking the waters
• Limited effectiveness, with only about 1 in 8 women going into labor within 48 hours 1
• Cramping or discomfort without progressing to active labor It's essential to note that the effectiveness of a membrane sweep is not guaranteed, and women should discuss their specific situation with their healthcare provider to determine if the procedure aligns with their birth preferences and medical circumstances. According to the ARRIVE trial, elective induction of labor at 39 weeks can be a reasonable option for low-risk nulliparous women, but the decision should be made on a case-by-case basis 1. Women should weigh the pros and cons of a membrane sweep and consider their individual circumstances before making a decision.

From the Research

Pros of Membrane Sweeping at 39 Weeks

• Membrane sweeping may be effective in achieving a spontaneous onset of labour, with women randomised to membrane sweeping being more likely to experience spontaneous onset of labour (average risk ratio (aRR) 1.21,95% confidence interval (CI) 1.08 to 1.34,17 studies, 3170 participants, low-certainty evidence) 2
• It potentially reduces the incidence of formal induction of labour (aRR 0.73,95% CI 0.56 to 0.94,16 studies, 3224 participants, low-certainty evidence) 2
• Membrane sweeping has a high success rate in inducing labour, with 86.4% of postdate women experiencing labour onset after membrane sweeping 3
• It can be safe for both the mother and the baby, with a low rate of maternal and fetal complications 3
• Twice-weekly membrane sweeping is more effective than once-weekly or no sweeping in preventing prolonged pregnancy, without added adverse feto-maternal outcomes 4

Cons of Membrane Sweeping at 39 Weeks

• The evidence for the effectiveness of membrane sweeping in achieving a spontaneous onset of labour is of low certainty 2
• There may be little to no difference between groups for caesareans, spontaneous vaginal birth, maternal death or serious morbidity, and neonatal perinatal death or serious morbidity 2
• Membrane sweeping may not be effective in reducing the incidence of caesarean section or improving vaginal birth after caesarean section (VBAC) rates 5
• Some women may experience discomfort or pain during the procedure
• There is limited evidence on the optimal number of membrane sweeps and timings to facilitate induction of labour 2

Outcomes of Membrane Sweeping at 39 Weeks

• The sweeping to delivery interval can range from 7.4 days for twice-weekly sweeping to 10.6 days for the control group 4
• The incidence of prolonged pregnancy can be reduced with membrane sweeping, with 11.7% of women in the twice-weekly group experiencing prolonged pregnancy compared to 32.3% in the control group 4
• Membrane sweeping can be associated with a low rate of maternal and fetal complications, including postpartum hemorrhage, sepsis, and neonatal intensive care unit admission 3