Indiana University School of Medicine, Indianapolis, Indiana; Washington University in St. Louis, St. Louis, Missouri; Perelman School of Medicine, University of Pennsylvania; Philadelphia, Pennsylvania; University Hospitals Cleveland and Case Western Reserve University School of Medicine, Cleveland, Ohio; University of Utah, Salt Lake City, Utah; University of Southern California, Los Angeles, California; and University of Hawaii, Honolulu, Hawaii.
Obstet Gynecol. 2022 Apr 1;139(4):554-560. doi: 10.1097/AOG.0000000000004703. Epub 2022 Mar 10.
To assess whether obesity is associated with increased time to pregnancy in a cohort of participants who were stopping their contraceptive method to attempt pregnancy.
We performed a secondary analysis of the FACT (Fertility After Contraceptive Termination) study. This prospective analysis included 432 participants, aged 18-35 years, who discontinued contraception to become pregnant, were sexually active with a male partner, and provided pregnancy status data within the first 12 months in the study. The primary outcome, time to pregnancy, was measured beginning with discontinuation of contraception to estimated pregnancy date. We used Cox proportional hazard models to assess associations of normal (lower than 25.0), overweight (25.0-29.9), and obese (30 or higher) body mass index (BMI) and time to pregnancy while controlling for potential confounding factors.
After adjusting for confounders, participants with BMIs 30 or higher were noted to have prolonged time to pregnancy compared with those with BMIs lower than 25 (adjusted hazard ratio [aHR] 0.62; 95% CI 0.44-0.89). The median time to pregnancy for participants with normal BMIs was 5.3 months (95% CI 3.8-6.4) compared with 8.2 months (95% CI 6.8-10.8) for participants with obesity. Pregnancy rates at 1 year were 76.4% (95% CI 69.7-82.6%), 69.5% (95% CI 60.5-78.1%), and 59.1% (95% CI 51.0-67.4%) for participants with BMIs lower than 25, 25-29.9, and 30 or higher, respectively. Menstrual irregularity was also associated with decreased fertility (aHR 0.67; 95% CI 0.46-0.97).
Compared with participants with normal BMIs, we observed increased time to pregnancy for participants with obesity stopping contraception with the intention to become pregnant. Understanding the reasons for this association will be helpful to inform patients and guide clinical practice.
The FACT Study was funded, in part, by Bayer, CooperSurgical, and the Society of Family Planning.
评估在一组停止避孕方法以尝试怀孕的参与者中，肥胖是否与怀孕时间延长有关。
我们对 FACT（避孕终止后的生育力）研究进行了二次分析。这项前瞻性分析包括 432 名年龄在 18-35 岁之间的参与者，他们停止避孕以怀孕，与男性伴侣保持性行为，并在研究的前 12 个月内提供妊娠状态数据。主要结局，即妊娠时间，从停止避孕到估计的妊娠日期开始测量。我们使用 Cox 比例风险模型来评估正常（低于 25.0）、超重（25.0-29.9）和肥胖（30 或更高）体重指数（BMI）与妊娠时间的关联，同时控制潜在的混杂因素。
在调整混杂因素后，与 BMI 低于 25 的参与者相比，BMI 为 30 或更高的参与者怀孕时间延长（调整后的危险比[aHR]0.62；95%置信区间[CI]0.44-0.89）。正常 BMI 参与者的中位妊娠时间为 5.3 个月（95%CI 3.8-6.4），而肥胖参与者的中位妊娠时间为 8.2 个月（95%CI 6.8-10.8）。BMI 低于 25、25-29.9 和 30 或更高的参与者在 1 年内的妊娠率分别为 76.4%（95%CI 69.7-82.6%）、69.5%（95%CI 60.5-78.1%）和 59.1%（95%CI 51.0-67.4%）。月经不规律也与生育力下降有关（aHR 0.67；95%CI 0.46-0.97）。
与正常 BMI 的参与者相比，我们观察到肥胖的参与者在停止避孕以尝试怀孕时怀孕时间延长。了解这种关联的原因将有助于为患者提供信息并指导临床实践。
FACT 研究部分由拜耳、库珀外科和计划生育协会资助。
