Su Xiu Juan, Huang Shi Jia, Li Xiang, Du Qiao Ling
Clinical Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China.
Department of Obstetrics, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China.
Obes Facts. 2020;13(2):237-244. doi: 10.1159/000506688. Epub 2020 Mar 27.
The association between obesity before pregnancy and preterm birth varies with age and ethnicity.
To study the association between early body mass index (BMI) and risk of preterm birth in Chinese women.
This was a hospital-based retrospective cohort study including 36,596 Chinese women who gave birth to a live singleton infant from 2015 to 2018. Women were classified as underweight (BMI <18.5), normal weight (BMI 18.5 to <23), overweight (BMI 23 to <27.5), or obese (BMI ≥27.5) according to the most recent criteria for Asian women. Multivariate log-binomial regression models were used to estimate the relative risks (RRs) and 95% confidence intervals (95% CIs) for preterm birth among different groups.
Compared to women with normal weight, women with overweight or obesity before pregnancy had an increased risk of preterm birth; the RRs and 95% CIs were 1.22 (95% CI: 1.08-1.37) and 1.30 (95% CI: 1.01-1.69), respectively. The greatest risk of extremely preterm birth was observed in obese women. The estimators were robust when considering the maternal age and rate of gestational weight gain (GWG) during pregnancy.
Women with overweight and obesity had an increased risk of preterm birth regardless of GWG in early pregnancy. Our study suggests that it is beneficial to lose weight before conception for both overweight and obese women who plan to become pregnant.
孕前肥胖与早产之间的关联因年龄和种族而异。
研究中国女性早期体重指数（BMI）与早产风险之间的关联。
这是一项基于医院的回顾性队列研究，纳入了2015年至2018年期间分娩单胎活婴的36596名中国女性。根据亚洲女性的最新标准，将女性分为体重过轻（BMI<18.5）、正常体重（BMI 18.5至<23）、超重（BMI 23至<27.5）或肥胖（BMI≥27.5）。使用多变量对数二项回归模型估计不同组早产的相对风险（RRs）和95%置信区间（95% CIs）。
与正常体重的女性相比，孕前超重或肥胖的女性早产风险增加；RRs和95% CIs分别为1.22（95% CI：1.08 - 1.37）和1.30（95% CI：1.01 - 1.69）。肥胖女性发生极早早产的风险最高。在考虑孕妇年龄和孕期体重增加率（GWG）时，估计值是稳健的。
无论孕早期的GWG如何，超重和肥胖女性的早产风险都会增加。我们的研究表明，对于计划怀孕的超重和肥胖女性，在受孕前减肥是有益的。
