Gunnarsson Björn, Skogvoll Eirik, Jónsdóttir Ingibjörg Hanna, Røislien Jo, Smárason Alexander Kr
Department of Research, Norwegian Air Ambulance Foundation, Holterveien 24, 1448, Drøbak, Norway.
Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
BMC Pregnancy Childbirth. 2017 Jun 12;17(1):183. doi: 10.1186/s12884-017-1345-1.
Labor that progresses faster than anticipated may lead to unplanned out-of-hospital births. With the aim to improve planning of transportation to birthing institutions, this study investigated predictors of time to completion for the first stage of labor conditional on cervical opening (conditional time) in multiparous women at term.
We performed a retrospective analysis of partograms for women in Robson's group 3 who delivered at one hospital from 2003 to 2013. A generalized additive mixed model was fitted, accounting for possible non-linear relationships between the predictor variables and outcome, e.g. the time from each cervical measurement to full dilation, using multiple measurements for each woman. The following predictors were included: cervical dilation (cm), parity (1, 2, or ≥3 previous vaginal births), oxytocin infusion (no/yes), epidural (no/yes), maternal age (years), maternal height (cm), body mass index (BMI, kg/m), birthweight (kg), spontaneous rupture of membranes (no/yes). A modified regression model with gestational age (days) instead of birthweight was used to predict conditional time to full cervical dilation for combinations of the most relevant predictors.
A total of 1753 partograms were included in the analysis. The strongest predictors were birthweight, epidural and oxytocin use, and spontaneous rupture of membranes, along with cervical measurements. For birthweight, there was an almost 40% increase in time to full cervical dilation for each 1-kg increment. Conditional time was on average 23% longer in cases with epidural use and 53% longer in cases requiring oxytocin augmentation. Spontaneous rupture of the membranes shortened conditional time by 31%. Maternal age was not associated with the outcome, while increasing BMI and parity modestly reduced conditional time.
Higher parity, lower fetal weight (gestational age), and spontaneous rupture of the membranes are associated with more rapid labor.
产程进展比预期更快可能导致意外的院外分娩。为了改善前往分娩机构的交通规划，本研究调查了足月经产妇第一产程完成时间（条件时间）的预测因素，该时间以宫颈扩张情况为条件。
我们对2003年至2013年在一家医院分娩的罗布森3组女性的产程图进行了回顾性分析。采用广义相加混合模型，考虑预测变量与结局之间可能存在的非线性关系，例如从每次宫颈测量到完全扩张的时间，对每位女性使用多次测量数据。纳入的预测因素如下：宫颈扩张程度（厘米）、产次（1次、2次或≥3次既往阴道分娩）、缩宫素输注（未使用/使用）、硬膜外麻醉（未使用/使用）、产妇年龄（岁）、产妇身高（厘米）、体重指数（BMI，千克/米²）、出生体重（千克）、胎膜早破（未发生/发生）。使用一个以孕周（天）而非出生体重的改良回归模型来预测最相关预测因素组合下宫颈完全扩张的条件时间。
分析共纳入1753份产程图。最强的预测因素是出生体重、硬膜外麻醉和缩宫素使用、胎膜早破以及宫颈测量值。对于出生体重，每增加1千克，宫颈完全扩张的时间几乎增加40%。使用硬膜外麻醉的病例条件时间平均延长23%，需要缩宫素加强宫缩的病例条件时间延长53%。胎膜早破使条件时间缩短31%。产妇年龄与结局无关，而BMI增加和产次增加会适度缩短条件时间。
产次增加、胎儿体重较低（孕周）以及胎膜早破与产程更快相关。
