Departments of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois, George Washington University Biostatistics Center, Washington, DC, MetroHealth Medical Center-Case Western Reserve University, Cleveland, Ohio, Yale University, New Haven, Connecticut, Columbia University, New York, New York, University of Utah Health Sciences Center, Salt Lake City, Utah, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, University of Texas Southwestern Medical Center, Dallas, Texas, University of Pittsburgh, Pittsburgh, Pennsylvania, The Ohio State University, Columbus, Ohio, University of Alabama at Birmingham, Birmingham, Alabama, University of Texas Medical Branch, Galveston, Texas, Wayne State University, Detroit, Michigan, Brown University, Providence, Rhode Island, University of Texas Health Science Center at Houston-Children's Memorial Hermann Hospital, Houston, Texas, and Oregon Health & Science University, Portland, Oregon.
Obstet Gynecol. 2020 Mar;135(3):535-541. doi: 10.1097/AOG.0000000000003707.
To examine whether the decision and indications for performing intrapartum cesarean delivery vary by time of day.
We conducted a secondary analysis of a multicenter observational cohort of 115,502 deliveries (2008-2011), including nulliparous women with term, singleton, nonanomalous live gestations in vertex presentation who were attempting labor. Those who attempted home birth, or underwent cesarean delivery scheduled or decided less than 30 minutes after admission were excluded. Time of day was defined as cesarean delivery decision time among those who delivered by cesarean and delivery time among those who delivered vaginally, categorized by each hour of a 24-hour day. Primary outcomes were decision to perform cesarean delivery and the indications for cesarean delivery (labor dystocia, nonreassuring fetal status, or other indications). Secondary outcomes included whether a dystocia indication adhered to standards promoted to reduce cesarean delivery rates. Bivariate analyses were performed using χ and Kruskal-Wallis tests for categorical and continuous outcomes, respectively, and generalized additive models with smoothing splines explored nonlinear associations without adjustment for other factors.
Seven thousand nine hundred fifty-six (22.1%) of 36,014 eligible women underwent cesarean delivery. Decision for cesarean delivery (P<.001) decreased from midnight (21.2%) to morning, reaching a nadir at 10:00 (17.9%) and subsequently rising to peak at 21:00 (26.2%). The frequency of cesarean delivery for dystocia also was significantly associated with time of day (P<.001) in a pattern mirroring overall cesarean delivery. Among cesarean deliveries for dystocia (n=5,274), decision for cesarean delivery at less than 5 cm dilation (P<.001), median duration from 5 cm dilation to cesarean delivery decision (P=.003), and median duration from complete dilation to cesarean delivery decision (P=.014) all significantly differed with time of day. The frequency of nonreassuring fetal status and "other" indications were not significantly associated with time of day (P>.05).
Among nulliparous women who were attempting labor at term, the decision to perform cesarean delivery, particularly for dystocia, varied with time of day. Some of these differences correlate with labor management differences, given the changing frequency of latent phase cesarean delivery and median time in active phase.
研究产程中施行剖宫产的决策和指征是否随时间而变化。
我们对一项多中心观察性队列研究中的 115502 例分娩（2008-2011 年）进行了二次分析，包括初产妇、足月、单胎、头位、非畸形活胎、尝试自然分娩的患者。那些试图在家分娩或在入院后 30 分钟内计划或决定行剖宫产的患者被排除在外。时间定义为行剖宫产的患者的剖宫产决策时间，以及行阴道分娩的患者的分娩时间，按照 24 小时制的每小时分类。主要结局为施行剖宫产的决策以及剖宫产的指征（产程延长、胎儿情况不稳定或其他指征）。次要结局包括产程延长的指征是否符合降低剖宫产率的标准。对于分类和连续结果，分别使用 χ2 和 Kruskal-Wallis 检验进行了双变量分析，并且使用平滑样条的广义加性模型探索了非线性关联，而没有对其他因素进行调整。
36014 例符合条件的产妇中，7956 例（22.1%）接受了剖宫产。行剖宫产的决策（P<.001）从午夜（21.2%）下降到上午，在 10：00 时达到最低点（17.9%），随后上升至 21：00 时的高峰（26.2%）。产程延长行剖宫产的频率也与时间显著相关（P<.001），呈与总体剖宫产一致的模式。在因产程延长而行剖宫产的 5274 例患者中，在宫口扩张不足 5cm 时行剖宫产的决策（P<.001）、从宫口扩张 5cm 到决定行剖宫产的中位时间（P=.003）和从完全宫口扩张到决定行剖宫产的中位时间（P=.014）均随时间而显著不同。胎儿情况不稳定和“其他”指征的频率与时间无显著相关性（P>.05）。
在尝试足月自然分娩的初产妇中，行剖宫产的决策，特别是因产程延长而行剖宫产的决策，随时间而变化。由于潜伏期剖宫产的频率和活跃期的中位时间发生变化，这些差异中的一些与产程管理的差异相关。
