Anthropogenic climate change poses a disproportional burden to fetal growth in low- and middle-income countries

Low- and middle-income countries (LMICs) are vulnerable to climate change and associated extreme temperatures, where the health of pregnant women and fetuses could be particularly affected. However, the extent to which anthropogenic climate change contributes to their health has not been documented. Utilizing 451,252 mother-infant pairs from 31 LMICs during 1990–2014, we show highly robust and spatially-heterogeneous associations between pregnancy extreme temperature exposure and the increased risk of reduced birth weight and low birth weight (LBW). Anthropogenic climate change contributed approximately 68.05%, 86.41%, and 76.79% of extreme heat-related LBWs in Southern Asia, Western Africa, and Eastern Africa, respectively, whereas it reduced extreme cold-related LBWs in Central, Eastern, and Southern Africa. The exposure-response relationship and the contribution from anthropogenic climate change are determined largely by the climate mean states in different regions. Our study provides compelling evidence that anthropogenic climate change disproportionately modulates extreme temperature-related fetal growth in LMICs.