Maternal exposure to extreme high‐temperature, particulate air pollution and macrosomia in 14 countries of Africa

Abstract

SummaryBackgroundMacrosomia has increased rapidly worldwide in the past few decades, with a huge impact on health. However, the effect of PM2.5and extreme high‐temperature (EHT) on macrosomia has been ignored.ObjectiveThis study aimed to explore the association between maternal exposure to EHT, PM2.5and macrosomia based on the Seventh Demographic and Health Survey (DHS) in 14 countries of Africa.MethodsThe study included detailed demographic information on 106 382 births and maternal. Satellite inversion models estimated monthly mean PM2.5and mean surface temperature of 2 m (SMT2m). Macrosomia was defined as the birth weight ≥ 4000 g. We used a Cox proportional risk regression model to estimate the association between PM2.5, EHT and macrosomia. We further explored the susceptibility of exposure to EHT and PM2.5at different pregnancy periods to macrosomia, and plotted the expose‐response curve between PM2.5and macrosomia risk using a restricted cubic spline function. In addition, the Interplot model was used to investigate the interaction between EHT and PM2.5on macrosomia. Finally, some potential confounding factors were analysed by stratification.ResultsThere was the positive association between EHT, PM2.5and macrosomia, and the risk of macrosomia with the increase in concentrations of PM2.5without clear threshold. Meanwhile, EHT and PM2.5had a higher effect on macrosomia in middle/later and early/middle stages of pregnancy, respectively. There was a significant interaction between EHT and PM2.5on macrosomia.ConclusionsMaternal exposure to EHT, PM2.5during pregnancy was associated with an increased risk of macrosomia in Africa.