Prostaglandin vaginal gel induction of labor comparing amniotomy with repeat prostaglandin gel

Published:August 04, 2015DOI:


      The purpose of this study was to compare 2 inductions of labor protocols.

      Study Design

      Women with live singleton pregnancies at ≥37 + 0 weeks gestation who were booked for prostaglandins 2 (PGE2) vaginal gel induction with a modified Bishop’s score of <7 were eligible for inclusion. After an evening dose of PGE2 vaginal gel, women were assigned randomly the next morning into the amniotomy or repeat-PGE2 group. The amniotomy group underwent artificial rupture of membranes (ARM), regardless of modified Bishop’s score, and received further PGE2 doses only if ARM was not technically possible. The repeat-PGE2 group received further PGE2 (to a maximum of 3 doses) until a modified Bishop’s score ≥7 occurred, when an ARM was performed. In both groups, Syntocinon was commenced once membranes were ruptured. The primary outcome measure was time from commencement of induction until birth.


      Two hundred forty-five women were assigned randomly into either the amniotomy (n = 121) or repeat-PGE2 group (n = 124). The time for induction of labor–to-birth was >5 hours shorter in the amniotomy group (24.8 vs 30.0 hours; mean difference, 5.2 h; 95% confidence interval, –2.5 to –7.8). Fewer women in the amniotomy group remained undelivered after 24 hours (47.1% vs 67.7%; P < .01). However, the likelihood of an in-hours birth and the length of hospital stay were no different between the groups. There was no difference in the mode of birth or any of the secondary outcomes.


      After an initial dose of PGE2 vaginal gel, an amniotomy (once technically possible) is associated with a shorter induction of labor–to-birth time compared with the use of repeat doses of PGE2. Administering more PGE2 with the aim of starting contractions or making the cervix “more favorable,” appears to have no clinical advantage.

      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


        • Laws P.
        • Sullivan E.
        Australia’s mothers and babies.
        Australian Institute of Health and Welfare, Canberra, Australia2010
        • National Institute of Clinical Excellence
        Induction of labour clinical guideline.
        NICE, London2008
        • American College of Obstetricians and Gynecologists
        Induction of labor. ACOG Practice Bulletin no. 107.
        Obstet Gynecol. 2009; 114: 386-397
        • World Health Organization
        WHO recommendations for induction of labour.
        Department of Reproductive Health and Research, Geneva2011
        • Thomas J.
        • Fairclough A.
        • Kavanagh J.
        • Kelly A.J.
        Vaginal prostaglandin (PGE2 and PGF2a) for induction of labour at term.
        Cochrane Database Syst Rev. 2014; 6: CD003101
      1. Induction of labour Clinical Guideline. Queensland Government, 2011. Available at: Accessed August 27, 2015.

      2. Induction of Labour Techniques - Clinical Guideline. Government of South Australia, 2013. Available at: Accessed August 27, 2015.

      3. Induction of Labour with Prostaglandin E2 Vaginal Gel (Prostin) Clinical Practice Guideline Victorian Government, 2014. Available at:$FILE/induction_of_labour_with_prostaglandin_e2_pge2_vaginal_gel_prostin.pdf. Accessed August 27, 2015.

      4. Use of prostaglandins for cervical ripening prior to the induction of labour. RANZCOG, 2012. Available at: Accessed August 27, 2015.

        • MacKenzie I.Z.
        • Burns E.
        Randomised trial of one versus two doses of prostaglandin E2 for induction of labour: 1. clinical outcome.
        BJOG. 1997; 104: 1062-1067
        • Gijsen R.
        • Hukkelhoven C.W.
        • Schipper C.M.
        • Ogbu U.C.
        • de Bruin-Kooistra M.
        • Westert G.P.
        Effects of hospital delivery during off-hours on perinatal outcome in several subgroups: a retrospective cohort study.
        BMC Pregnancy Childbirth. 2012; 12: 92
        • De Graaf J.P.
        • Ravelli A.C.
        • Visser G.H.
        • et al.
        Increased adverse perinatal outcome of hospital delivery at night.
        BJOG. 2010; 117: 1098-1107
        • Armijo-Olivo S.
        • Warren S.
        • Magee D.
        Intention to treat analysis, compliance, drop-outs and how to deal with missing data in clinical research: a review.
        Phys Ther Rev. 2009; 14: 36-49
        • Marley J.
        Editorial: efficacy, effectiveness, efficiency.
        Aust Prescr. 2000; 23: 114-115
        • Chua S.
        • Arulkumaran S.
        • Yap C.
        • Selamat N.
        • Ratnam S.S.
        Premature rupture of membranes in nulliparas at term with unfavorable cervices: a double-blind randomized trial of prostaglandin and placebo.
        Obstet Gynecol. 1995; 86: 550-554
        • Doany W.
        • McCarty J.
        Outpatient management of the uncomplicated postdate pregnancy with intravaginal prostaglandin E2 gel and membrane stripping.
        J Matern Fetal Med. 1997; 6: 71-78
        • Rayburn W.
        • Gosen R.
        • Ramadei C.
        • Woods R.
        • Scott Jr., J.
        Outpatient cervical ripening with prostaglandin E2 gel in uncomplicated postdate pregnancies.
        Am J Obstet Gynecol. 1988; 158: 1417-1423
        • Egarter C.
        • Kofler E.
        • Fitz R.
        • Husslein P.
        Is induction of labor indicated in prolonged pregnancy? Results of a prospective randomised trial.
        Gynecol Obstet Invest. 1989; 27: 6-9
        • Mahmood T.A.
        • Dick M.J.
        • Smith N.C.
        • Templeton A.A.
        Role of prostaglandin in the management of prelabour rupture of the membranes at term.
        BJOG. 1992; 99: 112-117
        • Ohel G.
        • Rahav D.
        • Rothbart H.
        • Ruach M.
        Randomised trial of outpatient induction of labor with vaginal PGE2 at 40-41 weeks of gestation versus expectant management.
        Arch Gynecol Obstet. 1996; 258: 109-112
        • Kravet S.J.
        • Levine R.B.
        • Rubin H.R.
        • Wright S.M.
        Discharging patients earlier in the day: a concept worth evaluating.
        Health Care Manag (Frederick). 2007; 26: 142-146
        • Powell E.S.
        • Khare R.K.
        • Venkatesh A.K.
        • Van Roo B.D.
        • Adams J.G.
        • Reinhardt G.
        The relationship between inpatient discharge timing and emergency department boarding.
        J Emerg Med. 2012; 42: 186-196
        • Shepperd S.
        • Lannin N.A.
        • Clemson L.M.
        • McCluskey A.
        • Cameron I.D.
        • Barras S.L.
        Discharge planning from hospital to home.
        Cochrane Database Syst Rev. 2013; 1: CD000313