Department of Preventive Medicine, School of Public Health, Guangzhou Medical University, Guangzhou, China
Faculty of Education, Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK.
BMJ Open Diabetes Res Care. 2021 Feb;9(1). doi: 10.1136/bmjdrc-2020-001641.
Associations of pre-pregnancy impaired fasting glucose (IFG) and body mass index (BMI) with large for gestational age (LGA) and preterm birth (PTB) have been poorly understood. We aimed to investigate the associations of maternal BMI, separately and together with pre-pregnancy IFG, with LGA and PTB in Chinese population. We also aimed to quantify these associations by maternal age.
This was a retrospective cohort study of women from the National Free Preconception Health Examination Project with singleton birth from 121 counties/districts in 21 cities of Guangdong Province, China, from January 1, 2013 to December 31, 2017. Women were included if they did not have pre-existing chronic diseases (diabetes, hypertension, etc). Participants were divided into eight groups according to their BMI (underweight (BMI <18.5 kg/m), normal weight (18.5-23.9 kg/m), overweight (24.0-27.9 kg/m), and obesity (≥28.0 kg/m)) and pre-pregnancy fasting glucose status (normoglycemia (fasting glucose concentration <6.1 mmol/L) and IFG (6.1-7.0 mmol/L)). Adjusted incidence risk ratios (aIRRs) and 95% CIs of LGA, severe LGA, PTB and early PTB were estimated.
We included 634 030 women. The incidences of LGA, severe LGA, PTB and early PTB for the study population were 7.1%, 2.5%, 5.1% and 1.1%, respectively. Compared with normal weight mothers with normoglycemia, overweight and obese mothers irrespective of IFG had a higher risk of LGA (eg, obesity with IFG aIRR 1.85 (1.60-2.14)) and severe LGA (eg, obesity with IFG 2.19 (1.73-2.79)). The associations of BMI and pre-pregnancy fasting glucose status with LGA were similar found among women of all age groups. Underweight with normoglycemia had 6.0% higher risk of PTB (1.06 (1.03-1.09)) and 8.0% higher risk of early PTB (1.08 (1.02-1.17)), underweight with IFG had 14.0% higher risk of PTB (1.14 (1.02-1.27)), and obese mothers with IFG had 45.0% higher risk of PTB (1.45 (1.18-1.78)). The associations of BMI and pre-pregnancy fasting glucose status with PTB differed by maternal age.
Overweight and obesity regardless of IFG were associated with an increased risk of LGA, and these associations were similarly observed among mothers of all age groups. Underweight regardless of IFG, and obesity with IFG were associated with an increased risk of PTB, but the associations differed by maternal age. Findings from this study may have implications for risk assessment and counselling before pregnancy.
孕前空腹血糖受损（IFG）和体重指数（BMI）与巨大儿（LGA）和早产（PTB）的关联尚未得到充分理解。我们旨在研究中国人群中母亲 BMI，单独和与孕前 IFG 一起，与 LGA 和 PTB 的关联。我们还旨在通过母亲年龄来量化这些关联。
这是一项回顾性队列研究，纳入了来自广东省 21 个城市 121 个县/区的参加国家免费孕前健康检查项目的单胎妊娠女性，研究时间为 2013 年 1 月 1 日至 2017 年 12 月 31 日。纳入的女性没有患慢性病（糖尿病、高血压等）。参与者根据 BMI（体重不足（BMI<18.5kg/m2）、正常体重（18.5-23.9kg/m2）、超重（24.0-27.9kg/m2）和肥胖（≥28.0kg/m2））和孕前空腹血糖状况（正常血糖（空腹血糖浓度<6.1mmol/L）和 IFG（6.1-7.0mmol/L））分为八组。估计了 LGA、重度 LGA、PTB 和早期 PTB 的调整后的发病率风险比（aIRR）和 95%置信区间。
我们纳入了 634030 名女性。研究人群中 LGA、重度 LGA、PTB 和早期 PTB 的发生率分别为 7.1%、2.5%、5.1%和 1.1%。与正常体重且血糖正常的母亲相比，无论 IFG 如何，超重和肥胖母亲的 LGA 风险更高（例如，肥胖伴 IFG aIRR 1.85（1.60-2.14））和重度 LGA（例如，肥胖伴 IFG 2.19（1.73-2.79））。在所有年龄组的女性中，BMI 和孕前空腹血糖状况与 LGA 的关联相似。血糖正常的体重不足女性发生 PTB 的风险高 6.0%（1.06（1.03-1.09）），发生早期 PTB 的风险高 8.0%（1.08（1.02-1.17）），IFG 伴体重不足的女性发生 PTB 的风险高 14.0%（1.14（1.02-1.27）），IFG 伴肥胖的母亲发生 PTB 的风险高 45.0%（1.45（1.18-1.78））。BMI 和孕前空腹血糖状况与 PTB 的关联因母亲年龄而异。
无论 IFG 如何，超重和肥胖都与 LGA 风险增加相关，并且在所有年龄组的母亲中都观察到了这些关联。无论 IFG 如何，体重不足以及 IFG 伴肥胖都与 PTB 风险增加相关，但关联因母亲年龄而异。本研究结果可能对妊娠前的风险评估和咨询具有重要意义。
