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We thank Drs Feng and Chen for their letter and their interest in our study. In our meta-analysis of randomized trials,1De Vivo V. Carbone L. Saccone G. et al.Early amniotomy after cervical ripening for induction of labor: a systematic review and meta-analysis of randomized controlled trials.Am J Obstet Gynecol. 2019 Aug 6; (pii: S0002-9378(19)30964-0. https://doi.org/10.1016/j.ajog.2019.07.049. [Epub ahead of print])Google Scholar including 4 trials with 1273 participants, we showed that after cervical ripening, with either Foley catheter or prostaglandins, routine amniotomy does not increase the risk of cesarean delivery, and reduces the interval from induction to delivery, compared to a policy of no amniotomy or late amniotomy at the time of active stage of labor. Drs Feng and Chen state that the nonsignificant difference in the primary outcome, that is, cesarean delivery, may be associated with a type I error, due to the small sample size. Although this is certainly possible, the sample size was 1273. Moreover, the relative risk of the pooled results for the primary outcome is very close to 1 (1.05 with 95% confidence interval of 0.71–1.56). Although we agree that trial sequential analysis is an important statistical tool, standard meta-analysis using the Mantel−Haenszel method is the gold standard for meta-analysis of randomized trials, also recommended by the Cochrane Collaboration.2Cochrane handbook for systematic reviews of interventions.https://training.cochrane.orgDate accessed: August 22, 2019Google Scholar There are several Cochrane reviews on the use of amniotomy in labor or for induction (with or without other interventions), with some of these reviews including more than 5500 women. None of them reports an increase in cesarean delivery.3Smyth R.M.D. Markham C. Dowswell T. Amniotomy for shortening spontaneous labour.Cochrane Database Syst Rev. 2013; 6: CD006167PubMed Google Scholar, 4Bricker L. Luckas M. Amniotomy alone for induction of labour.Cochrane Database Syst Rev. 2000; 4: CD002862Google Scholar, 5Howarth G. Botha D.J. Amniotomy plus intravenous oxytocin for induction of labour.Cochrane Database Syst Rev. 2001; 3: CD003250PubMed Google Scholar, 6Thomas J. Kelly A.J. Kavanagh J. Oestrogens alone or with amniotomy for cervical ripening or induction of labour.Cochrane Database Syst Rev. 2001; 4: CD003393Google Scholar, 7Wei S. Wo B.L. Qi H.P. et al.Early amniotomy and early oxytocin for prevention of, or therapy for, delay in first stage spontaneous labour compared with routine care.Cochrane Database Syst Rev. 2013; 8: CD006794PubMed Google Scholar In addition, although early amniotomy interferes with the physiological timing of fetal membrane rupture, several interventions interfering with the physiological natural time of delivery, for example, induction of labor at full term,8Saccone G. Della Corte L. Maruotti G.M. et al.Induction of labor at full-term in pregnant women with uncomplicated singleton pregnancy: a systematic review and meta-analysis of randomized trials.Acta Obstet Gynecol Scand. 2019; 98: 958-966Crossref PubMed Scopus (38) Google Scholar,9Saccone G. Berghella V. Induction of labor at full term in uncomplicated singleton gestations: a systematic review and metaanalysis of randomized controlled trials.Am J Obstet Gynecol. 2015; 213: 629-636Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar have been associated with a decrease, not an increase, in the incidence of cesarean delivery, and with improved maternal or perinatal outcome.10Grobman W.A. Rice M.M. Reddy U.M. et al.Labor induction versus expectant management in low-risk nulliparous women.N Engl J Med. 2018; 379: 513-523Crossref PubMed Scopus (520) Google Scholar We certainly wish for more research on amniotomy. Early amniotomy for induction of labor: a trial sequential analysisAmerican Journal of Obstetrics & GynecologyVol. 222Issue 1PreviewWe read with interest a systematic review and meta-analysis by De Vivo et al evaluating the effectiveness of early amniotomy vs late amniotomy or spontaneous rupture of membranes after cervical ripening.1 The authors found that women who were randomized to early amniotomy had a similar risk of cesarean delivery (31.1% vs 30.9%; relative risk, 1.05; 95% confidence interval, 0.71–1.56) compared to controls. They also found that women with early amniotomy had a shorter interval from induction to delivery of about 5 hours (mean difference −4.95 hours (95% confidence interval, −8.12 to −1.78), and found no other obstetric or perinatal outcomes between the early and late groups. Full-Text PDF