Objectives Smoking in pregnancy is associated with an increased risk of preterm birth (PTB), intrauterine growth restriction, placental abruption and perinatal death. The association between smoking and other delivery outcomes, such as chorioamnionitis, mode of delivery or postpartum hemorrhage (PPH), however, is insufficient as only few studies addressed these issues. The aim of the study was to evaluate the association between prenatal smoking and delivery outcomes in a large database, while controlling for confounding effects. Methods A retrospective population-based study using data from the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP‐NIS). A dataset of all deliveries between 2004 and 2014 (inclusively) was created. Our control group included all pregnant women who did not smoke during pregnancy, which was compared to pregnant women who smoked. A multivariate logistic analysis was conducted, adjusting for any statistically significant confounding effects. Results Our study identified 9,096,788 births between 2004 and 2014. Of which, 443,590 (4.8%) had a documented diagnosis of smoking. A significantly higher risk was found for PTB (odds ratio 1.39, CI 1.35–1.43), preterm premature rupture of membranes (odds ratio 1.52, CI 1.43–1.62) and small for gestational age (SGA) neonates (odds ratio 2.27, CI 2.19–2.35). The risks of preeclampsia (odds ratio 0.82, CI 0.78–0.85), chorioamnionitis (odds ratio 0.88, CI 0.83–0.4), PPH (odds ratio 0.94 CI 0.9–0.98) and operative vaginal delivery (odds ratio 0.9, CI 0.87–0.94) were lower among smokers. Conclusions This large database confirms the findings of previous smaller studies, according to which smoking decreases the risk of preeclampsia while increasing the risk of PTB and SGA neonates. The current study also revealed a decreased risk for PPH as well as for chorioamnionitis among pregnant smokers.

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吸烟与分娩结果之间的关系。对超过 900 万次交付的数据库进行评估

目的 妊娠期吸烟与早产 (PTB)、宫内生长受限、胎盘早剥和围产期死亡的风险增加有关。然而，吸烟与其他分娩结果（如绒毛膜羊膜炎、分娩方式或产后出血 (PPH)）之间的关联并不充分，因为只有少数研究解决了这些问题。该研究的目的是在一个大型数据库中评估产前吸烟与分娩结果之间的关联，同时控制混杂效应。方法 一项基于人群的回顾性研究，使用来自医疗保健成本和利用项目-全国住院患者样本 (HCUP-NIS) 的数据。创建了 2004 年至 2014 年（含）期间所有交付的数据集。我们的对照组包括所有在怀孕期间不吸烟的孕妇，与吸烟的孕妇相比。进行了多变量逻辑分析，调整了任何具有统计学意义的混杂效应。结果 我们的研究确定了 2004 年至 2014 年间 9,096,788 名新生儿。其中，443,590 人（4.8%）有吸烟的记录。PTB（优势比 1.39，CI 1.35–1.43）、早产胎膜早破（优势比 1.52，CI 1.43–1.62）和小于胎龄儿 (SGA) 新生儿（优势比 2.27，CI 2.19）的风险显着增加–2.35)。先兆子痫（优势比 0.82，CI 0.78–0.85）、绒毛膜羊膜炎（优势比 0.88，CI 0.83–0.4）、PPH（优势比 0.94，CI 0.9–0.98）和阴道手术（优势比 0.9，CI 0.87–0.94）的风险) 在吸烟者中较低。结论 这个大型数据库证实了先前较小研究的结果，据此，吸烟降低了先兆子痫的风险，同时增加了 PTB 和 SGA 新生儿的风险。目前的研究还显示，怀孕吸烟者患 PPH 和绒毛膜羊膜炎的风险降低。