Ramos Sebastian Z, Waring Molly E, Leung Katherine, Amir Nili S, Bannon Annika L, Moore Simas Tiffany A
Division of Research, Department of Obstetrics and Gynecology, the Division of Epidemiology of Chronic Diseases and Vulnerable Populations, Department of Quantitative Health Sciences, and the Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts.
Obstet Gynecol. 2017 Feb;129(2):311-320. doi: 10.1097/AOG.0000000000001847.
To examine rates of attempted and successful vacuum-assisted vaginal delivery by prepregnancy body mass index (BMI).
We conducted a retrospective cohort study of 2,084 women with singleton gestations needing operative delivery assistance and vacuum-eligible (fully dilated, +2 station or greater, 34 weeks of gestation or greater) using 2006-2014 inpatient records. Prepregnancy BMI was categorized as underweight (less than 18.5), normal weight (18.5 to less than 25), overweight (25 to less than 30), or obese (30 or greater). Logistic regression models estimated odds ratios (ORs) and 95% confidence intervals (CIs) of attempted and successful vacuum-assisted vaginal delivery by prepregnancy BMI adjusted for age, race, marital status, parity, diabetes, labor induction-augmentation, episiotomy, gestational age, and neonatal birth weight.
Thirty-nine percent of women requiring delivery assistance and eligible for a vacuum were overweight or obese, 79% had vacuum attempts, and 95.3% of attempted vacuum-assisted vaginal deliveries were successful. Compared with women who were normal weight prepregnancy (82.8%), women who were overweight or obese were less likely to have vacuum attempted (75.8%, OR 0.71, 95% CI 0.53-0.96 and 71.2%, OR 0.53, 95% CI 0.39-0.74, respectively). Among women with attempted vacuum-assisted vaginal delivery, successful delivery did not differ by prepregnancy BMI (92.6%, OR 0.54, 95% CI 0.21-1.37 for underweight; 94.5%, OR 1.07, 95% CI 0.57-2.00 for overweight; 96.3%, OR 1.09, 95% CI 0.51-2.33 for obese compared with 95.6% among normal-weight women).
Among women in need of operative delivery assistance, prepregnancy obesity was associated with lower likelihood of attempted vacuum-assisted vaginal delivery but, if attempted, success rates were similar to rates among normal-weight women. With significant morbidity of second-stage cesarean delivery in obese women, research should examine whether vacuum-assisted vaginal delivery may be appropriate for additional obese patients.
按孕前体重指数（BMI）检查真空辅助阴道分娩的尝试率和成功率。
我们利用2006 - 2014年住院记录，对2084名单胎妊娠且需要手术分娩辅助且符合真空吸引条件（宫口全开、胎头双顶径在坐骨棘平面下2cm或更低、孕周34周及以上）的女性进行了一项回顾性队列研究。孕前BMI分为体重过轻（低于18.5）、正常体重（18.5至低于25）、超重（25至低于30）或肥胖（30及以上）。逻辑回归模型估计了经年龄、种族、婚姻状况、产次、糖尿病、引产 - 催产、会阴切开术、孕周和新生儿出生体重调整后的孕前BMI与尝试及成功进行真空辅助阴道分娩的比值比（OR）和95%置信区间（CI）。
需要分娩辅助且符合真空吸引条件的女性中，39%超重或肥胖，79%尝试了真空吸引，95.3%的真空辅助阴道分娩尝试成功。与孕前体重正常的女性（82.8%）相比，超重或肥胖的女性尝试真空吸引的可能性较小（分别为75.8%，OR 0.71，95% CI 0.53 - 0.96和71.2%，OR 0.53，95% CI 0.39 - 0.74）。在尝试真空辅助阴道分娩的女性中，成功分娩率在孕前BMI方面无差异（体重过轻的女性为92.6%，OR 0.54，95% CI 0.21 - 1.37；超重女性为94.5%，OR 1.07，95% CI 0.57 - 2.00；肥胖女性为96.3%，OR 1.09，95% CI 0.51 - 2.33，而体重正常的女性为95.6%）。
在需要手术分娩辅助的女性中，孕前肥胖与尝试真空辅助阴道分娩的可能性较低相关，但如果尝试，成功率与体重正常的女性相似。鉴于肥胖女性二期剖宫产的发病率较高，研究应探讨真空辅助阴道分娩是否适用于更多肥胖患者。
