共3,062名女性被分配接受引产，3,044名被分配接受期待治疗。在引产组和期待治疗组新生儿中，主要结局的发生率分别为4.3%和5.4%（相对危险度，0.80；95%置信区间[CI]，0.64～1.00）。引产组的剖宫产率显著低于期待治疗组（18.6% vs. 22.2%；相对危险度，0.84；95% CI，0.76～0.93）。
低危未经产女性39周时引产未显著降低围生期复合不良结局的发生率，但显著降低了剖宫产率（由尤尼斯·肯尼迪·施莱佛国立儿童健康与人类发展研究所[Eunice Kennedy Shriver National Institute of Child Health and Human Development]资助；ARRIVE在ClinicalTrials.gov注册号为NCT01990612）。
William A. Grobman, M.D., Madeline M. Rice, Ph.D., Uma M. Reddy, M.D., M.P.H., Alan T.N. Tita, M.D., Ph.D., Robert M. Silver, M.D., Gail Mallett, R.N., M.S., C.C.R.C., Kim Hill, R.N., B.S.N., Elizabeth A. Thom, Ph.D., Yasser Y. El-Sayed, M.D., Annette Perez-Delboy, M.D., Dwight J. Rouse, M.D., George R. Saade, M.D., Kim A. Boggess, M.D., Suneet P. Chauhan, M.D., Jay D. Iams, M.D., Edward K. Chien, M.D., Brian M. Casey, M.D., Ronald S. Gibbs, M.D., Sindhu K. Srinivas, M.D., M.S.C.E., Geeta K. Swamy, M.D., Hyagriv N. Simhan, M.D., and George A. Macones, M.D., M.S.C.E. for the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network*
From the Department of Obstetrics and Gynecology, Northwestern University, Chicago (W.A.G., G.M.); University of Alabama at Birmingham, Birmingham (A.T.N.T.); University of Utah Health Sciences Center, Salt Lake City (R.M.S., K.H.); Stanford University, Stanford, CA (Y.Y.E.-S.); Columbia University, New York (A.P.-D.); Brown University, Providence, RI (D.J.R.); University of Texas Medical Branch, Galveston (G.R.S.), University of Texas Health Science Center at Houston, Children’s Memorial Hermann Hospital, Houston (S.P.C.), and University of Texas Southwestern Medical Center, Dallas (B.M.C.) — all in Texas; University of North Carolina at Chapel Hill, Chapel Hill (K.A.B.), and Duke University, Durham (G.K.S.) — both in North Carolina; Ohio State University, Columbus (J.D.I.), and MetroHealth Medical Center, Case Western Reserve University, Cleveland (E.K.C.) — both in Ohio; University of Colorado School of Medicine, Anschutz Medical Campus, Aurora (R.S.G.); University of Pennsylvania, Philadelphia (S.K.S.); University of Pittsburgh, Pittsburgh (H.N.S.) — both in Pennsylvania; Washington University, St. Louis (G.A.M.); the George Washington University Biostatistics Center, Washington, DC (M.M.R., E.A.T.); and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD (U.M.R.). Address reprint requests to Dr. Grobman at the Department of Obstetrics and Gynecology, Northwestern University, 250 E. Superior St., Suite 05-2175, Chicago, IL 60611, or at firstname.lastname@example.org. *A list of other members of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network is provided in the Supplementary Appendix, available at NEJM.org.
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