Blitz Matthew J, Rochelson Burton, Stork Leah B, Augustine Stephanie, Greenberg Meir, Sison Cristina P, Vohra Nidhi
Divisions of Maternal-Fetal Medicine.
Department of Obstetrics and Gynecology.
J Ultrasound Med. 2018 Mar;37(3):561-568. doi: 10.1002/jum.14362. Epub 2017 Aug 29.
To determine the effect, if any, of an increasing maternal body mass index (BMI) on sonographically diagnosed oligohydramnios in late gestation and how it subsequently affects obstetric and neonatal outcomes.
This retrospective cohort study evaluated all women with singleton gestations who had a sonographic examination at 40 to 42 weeks' gestational age at North Shore University Hospital from 2010 through 2013. Underweight women (prepregnancy BMI < 18.5 kg/m ) were excluded because of higher rates of oligohydramnios and fetal growth restriction. Patients were classified into 5 groups by late-pregnancy BMI. The primary variable of interest was the diagnosis of oligohydramnios (amniotic fluid index < 5 cm). Secondary variables of interest included the mode of delivery and indication for primary cesarean delivery. A multivariable logistic regression analysis was performed.
Oligohydramnios was identified in 189 of 1671 patients (11.3%). There was no significant difference in the amniotic fluid index between BMI groups. The rate of primary cesarean delivery increased with each successive BMI group (P < .001) such that women in the class III obesity group had an approximately 3-fold higher rate of primary cesarean delivery than women in the normal BMI group and a 2-fold higher rate than women in the overweight BMI group. In the final multivariable logistic regression model, a high BMI, nulliparity, and excessive gestational weight gain were associated with primary cesarean delivery. However, oligohydramnios did not contribute significantly to the model.
The maternal BMI is not associated with oligohydramnios in late gestation. An increasing maternal BMI significantly increases the risk of primary cesarean delivery.
确定孕晚期孕妇体重指数（BMI）增加对超声诊断羊水过少的影响（若有影响），以及其随后如何影响产科和新生儿结局。
这项回顾性队列研究评估了2010年至2013年在北岸大学医院孕40至42周接受超声检查的所有单胎妊娠妇女。体重过轻的妇女（孕前BMI＜18.5kg/m²）因羊水过少和胎儿生长受限发生率较高而被排除。根据孕晚期BMI将患者分为5组。主要关注变量为羊水过少的诊断（羊水指数＜5cm）。次要关注变量包括分娩方式和初次剖宫产指征。进行多变量逻辑回归分析。
1671例患者中有189例（11.3%）被诊断为羊水过少。BMI组间羊水指数无显著差异。随着BMI组别的依次升高，初次剖宫产率增加（P＜0.001），III级肥胖组妇女的初次剖宫产率比正常BMI组妇女高约3倍，比超重BMI组妇女高2倍。在最终的多变量逻辑回归模型中，高BMI、初产和孕期体重增加过多与初次剖宫产相关。然而，羊水过少对该模型没有显著贡献。
孕晚期孕妇BMI与羊水过少无关。孕妇BMI增加会显著增加初次剖宫产的风险。
