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Membrane Sweeping at Initiation of Formal Labor Induction
A Randomized Controlled Trial
Peng Chiong Tan,
MRCOG,

Reena Jacob,

MBBS,

and Siti Zawiah Omar,

MMed

OBJECTIVE: To determine the benefit of membrane sweeping at initiation of labor induction in conjunction with formal methods of labor induction. METHODS: Two hundred seventy-four women at term with a singleton fetus incephalic presentation and intact membranes were randomly assigned to receive membrane sweeping or no membrane sweeping at initiation of formal labor induction with either dinoprostone pessary or amniotomy. Outcome measures included mode of delivery, induction-to-delivery interval, dinosprostone dose, any oxytocin use and duration of oxytocin use in labor, visual analog score for pain associated withsweeping, and visual analog score for satisfaction with the birth process. RESULTS: Two hundred sixty-four women (136 sweep and 128 no sweep) had their data analyzed. Ten women (4 sweep and 6 no sweep) were excluded because of exclusion criteria infringements. Swept women had higher spontaneous vaginal delivery rate (69% compared with 56%, P .041), shorter induction to delivery interval (mean 14compared with 19 hours, P .003), fewer that required oxytocin use (46% compared with 59%, P .037), shorter duration of oxytocin infusion (mean 2.6 compared with 4.3 hours, P .001) and improved visual analog score for birth process satisfaction (mean 4.0 compared with 4.7, P .015). The reduction in dinoprostone dose used (mean 1.2 compared with 1.3, P .082) was not significant. Postsweeping visualanalog score for pain (mean 4.7 compared with 3.5, P < .001) was significantly increased. CONCLUSION: Membrane sweeping at initiation of labor induction increased the spontaneous vaginal delivery
From the Department of Obstetrics & Gynecology, University of Malaya, Kuala Lumpur, Malaysia. Corresponding author: Dr. Peng Chiong Tan, Department of Obstetrics & Gynecology, Faculty of Medicine,University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia; e-mail: pctan@um.edu.my. © 2006 by The American College of Obstetricians and Gynecologists. Published by Lippincott Williams & Wilkins. ISSN: 0029-7844/06

rate, reduced oxytocic drug use, shortened induction to delivery interval, and improved patient satisfaction.
(Obstet Gynecol 2006;107:569–77)

LEVEL OF EVIDENCE: I

nduction oflabor occurs in about 20% of term pregnancies but is associated with a lower rate of spontaneous vaginal delivery in comparison with spontaneously occurring labor.1 The physiologic basis of membrane sweeping leading to labor is well established and has been shown to release endogenous prostaglandins,2– 4 phospholipase A3 and oxytocin (Ferguson’s reflex).5 Uterine contraction frequency is alsoincreased by membrane sweeping.3 The release of prostaglandins can last at least 6 hours.4 Membrane sweeping alone is an effective but less efficient method of labor induction compared with more established methods such as vaginal prostaglandin or amniotomy with oxytocin infusion.6 – 8 A recent Cochrane meta-analysis of membrane sweeping trials concluded that although it reduces the number of womenprogressing to postterm gestation and the need for formal labor induction, sweeping is not associated with a reduction in cesarean or instrumental delivery, and it can cause discomfort and vaginal bleeding.8 We did a literature search on PubMed (http:// www.ncbi.nlm.nih.gov/entrez/query.fcgi) using search terms “membrane sweeping” or “membrane stripping” and “labor induction” on November 24, 2005,for studies in all languages published between January 1966 and November 2005 inclusive, looking for trials of membrane sweeping or membrane stripping and labor induction. Although many studies of membrane sweeping have been reported, these studies focus on attempts to reduce incidence of postdates and formal labor induction as identified in the Cochrane review.6 We found only 1 study that dealt...