Pre-Pregnancy Air Pollution Exposure Linked to Childhood Obesity Risk: Study

New Delhi: A new study has found that greater exposure to air pollution, particularly particulate matter (PM2.5, PM10) and nitrogen dioxide (NO2), in the three months before conception can increase the risk of childhood obesity up to two years after birth. The research, conducted by an international team from the US and China, highlights the critical impact of environmental exposures during the preconception period on long-term child health.

Published in the journal Environmental Research, the study examined 5,834 mother-child pairs recruited from maternity clinics in Shanghai. Unlike previous studies that linked air pollution exposure during pregnancy to respiratory and chronic health problems in children, this study focused on the preconception phase, typically defined as the three months before pregnancy begins.

According to the researchers, this period is significant as sperm and eggs are in their final stages of development, making them particularly vulnerable to environmental factors. The findings showed that increased exposure to PM2.5, PM10, and NO2 before conception correlated with higher body mass index (BMI) and BMI z-scores (BMIZ) in children.

Jiawen Liao, postdoctoral research associate at the Keck School of Medicine, University of Southern California, stated, “These findings imply that the three months before conception are important, and individuals planning to have children should consider measures to reduce air pollution exposure to lower their children’s risk of obesity.”

Specifically, the study found that higher PM2.5 exposure before pregnancy was linked to a 0.078 increase in BMIZ at age two, while PM10 exposure was associated with a 0.093 kg/m² increase in BMI at the same age. From six months onwards, children exposed to higher levels of pollutants before conception exhibited faster weight, BMI, and BMIZ growth rates.

Though the study is observational, its implications are substantial, given the widespread nature of air pollution. “The risk of air pollution exposure on children’s obesity may be significant and could begin before pregnancy,” said Zhanghua Chen, assistant professor at USC.

The researchers emphasized the need for further studies but encouraged proactive measures to minimize exposure to air pollution during the preconception period.