Maternal Prepregnancy Overweight/Obesity and adverse pregnancy outcomes in twins: A Population-Based Cohort Study in China

Abstract

Abstract Background Overweight or obese before pregnancy can have adverse effects on the health of singleton pregnant women, but its potential impact on twin pregnant mothers and twins is still unclear. Material and methods This study collected clinical data of twin births and their mothers from 22 units in 12 regions of China between January 2018 and December 2020. The study used multiple logistic regression analysis, propensity score matching analysis, inverse probability weighting, and overlap weighting models to control confounding factors, and explored the effects of different prepregnancy body mass index on adverse pregnancy outcomes. Results Compared to prepregnancy normal weight, prepregnancy overweight/obesity increased the incidence of larger and smaller twin infants with 1-min Apgar score ≤ 7 (adjusted OR (95% CI): 1.60 (1.20–2.13) and 1.45 (1.09–1.92), respectively), as well as the incidence of hypertensive disorders of pregnancy and gestational diabetes (adjusted OR (95% CI): 1.85 (1.55–2.21) and 1.49 (1.27–1.74), respectively). These findings were consistent after propensity score matching analysis, inverse probability weighting, and overlapping weighting. Additionally, prepregnancy underweight reduced the rate of twins with 1-min Apgar score ≤ 7 (0.56 (0.32–0.92) and 0.58 (0.34–0.94), respectively). Different prepregnancy BMI did not have a significant impact on 5-minute Apgar score, birth weight discordance in twins, NICU admission, preterm birth or low birth weight. Conclusion Maternal overweight/obesity before pregnancy increases the incidence of hypertensive disorders of pregnancy and gestational diabetes in twin pregnancies, and also elevates the risk of twins having a low Apgar score. Therefore, it is imperative to manage weight before pregnancy and prepare for neonatal resuscitation during delivery.