Buccal vs vaginal misoprostol combined with Foley catheter for cervical ripening at term (the BEGIN trial): a randomized controlled trial

Published:February 19, 2021DOI:


      Combining pharmacologic agents with mechanical ripening achieves the shortest time to labor; however, there is no clear evidence on route of drug administration. Buccal administration of misoprostol has shown greater patient acceptance but remains understudied.


      This study aimed to evaluate the difference in time to delivery between buccal and vaginal administration of misoprostol along with a Foley catheter for induction of labor.

      Study Design

      The BEGIN trial (buccal vs vaginal misoprostol combined with Foley catheter for cervical ripening at term) was an institutional review board–approved, randomized clinical trial conducted from June 2019 to January 2020 comparing identical doses (25 μg) of buccal misoprostol and vaginal misoprostol along with a Foley catheter for induction of labor. Randomization was stratified by parity. Labor management was standardized among participants. Individuals undergoing induction of labor at ≥37 weeks with a singleton gestation and needing cervical ripening were included. Our primary outcome was time to delivery. Kruskal-Wallis, Pearson chi-squared, and Cox survival analyses with intent-to-treat principles were performed. A sample size of 216 was planned to detect a 4-hour reduction in delivery time.


      A total of 215 women (108 in the buccal drug administration group and 107 in the vaginal drug administration group) were randomized. The vaginal route of drug administration achieved a faster median time to delivery than the buccal route of drug administration (19.7 hours in the vaginal route vs 24.1 hours in the buccal route; P<.001). A greater percentage of women in the vaginal drug administration group delivered within 24 hours compared with the buccal drug administration group (65% vs 49%; P=.02). There was no difference in the cesarean delivery rate between the 2 groups (17% in the vaginal drug administration group vs 21% in the buccal drug administration group; P=.6). Individuals who received vaginal misoprostol with Foley catheter delivered 2 times faster than women who received buccal misoprostol with Foley catheter after censoring for cesarean delivery and adjusting for parity (hazard ratio, 2.13; 95% confidence interval, 1.44–3.17). There was no significant difference in maternal and neonatal outcomes.


      We found that vaginal administration of misoprostol was superior to buccal administration of misoprostol along with a Foley catheter for induction of labor. Furthermore, vaginal administration of misoprostol resulted in twice the chance of delivering earlier compared with buccal administration of misoprostol with no difference in cesarean delivery rates. Therefore, the vaginal route of administration of misoprostol should be preferred among individuals undergoing a combined pharmacologic and mechanical induction.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Obstetrics & Gynecology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Martin J.A.
        • Hamilton B.E.
        • Osterman M.J.K.
        • Driscoll A.K.
        Births: final data for 2018.
        Natl Vital Stat Rep. 2019; 68: 1-47
        • Levine L.D.
        • Downes K.L.
        • Elovitz M.A.
        • Parry S.
        • Sammel M.D.
        • Srinivas S.K.
        Mechanical and pharmacologic methods of labor induction: a randomized controlled trial.
        Obstet Gynecol. 2016; 128: 1357-1364
        • Haas D.M.
        • Daggy J.
        • Flannery K.M.
        • et al.
        A comparison of vaginal versus buccal misoprostol for cervical ripening in women for labor induction at term (the IMPROVE trial): a triple-masked randomized controlled trial.
        Am J Obstet Gynecol. 2019; 221: 259.e1-259.e16
        • Towns R.
        • Quinney S.K.
        • Pierson R.C.
        • Haas D.M.
        Survey of provider preferences regarding the route of misoprostol for induction of labor at term.
        AJP Rep. 2017; 7: e158-e162
      1. ACOG Practice Bulletin no. 107: induction of labor.
        Obstet Gynecol. 2009; 114: 386-397
      2. Committee Opinion no 700: methods for estimating the due date.
        Obstet Gynecol. 2017; 129: e150-e154
        • Harris P.A.
        • Taylor R.
        • Thielke R.
        • Payne J.
        • Gonzalez N.
        • Conde J.G.
        Research electronic data capture (REDCap)—a metadata-driven methodology and workflow process for providing translational research informatics support.
        J Biomed Inform. 2009; 42: 377-381
        • Carbone J.F.
        • Tuuli M.G.
        • Fogertey P.J.
        • Roehl K.A.
        • Macones G.A.
        Combination of Foley bulb and vaginal misoprostol compared with vaginal misoprostol alone for cervical ripening and labor induction: a randomized controlled trial.
        Obstet Gynecol. 2013; 121: 247-252
        • Selin L.
        • Wennerholm U.B.
        • Jonsson M.
        • et al.
        High-dose versus low-dose of oxytocin for labour augmentation: a randomised controlled trial.
        Women Birth. 2019; 32: 356-363
        • Macones G.A.
        • Cahill A.
        • Stamilio D.M.
        • Odibo A.O.
        The efficacy of early amniotomy in nulliparous labor induction: a randomized controlled trial.
        Am J Obstet Gynecol. 2012; 207: 403.e1-403.e5
        • Carlan S.J.
        • Blust D.
        • O’Brien W.F.
        Buccal versus intravaginal misoprostol administration for cervical ripening.
        Am J Obstet Gynecol. 2002; 186: 229-233
        • Allen R.
        • O’Brien B.M.
        Uses of misoprostol in obstetrics and gynecology.
        Rev Obstet Gynecol. 2009; 2: 159-168
        • Dorr M.L.
        • Pierson R.C.
        • Daggy J.
        • Quinney S.K.
        • Haas D.M.
        Buccal versus vaginal misoprostol for term induction of labor: a retrospective cohort study.
        Am J Perinatol. 2019; 36: 765-772