New Delhi: Exposure to air pollution during pregnancy may do far more than affect a mother’s health. A new study by researchers at AIIMS Delhi has found that fine particulate matter in polluted air can damage the placenta, restrict fetal growth, increase the risk of low birth weight and pregnancy complications, and may even affect a child’s development after birth.Published in EMBO Molecular Medicine, the study examined how urban particulate matter (PM2.5 and PM10) affects pregnancy through laboratory experiments, animal models and human data. Researchers found that tiny pollution particles can cross the placental barrier, trigger inflammation and oxidative stress, and interfere with the placenta’s ability to supply oxygen and nutrients to the developing baby.The team observed that exposure to urban particulate matter impaired key placental functions, including blood vessel formation, nutrient transport and fetal growth. In animal studies, pregnant rats exposed to pollution had smaller litters, abnormal placentas and babies with reduced birth weight and growth.The findings were supported by an analysis of 994 pregnancies from regions with different pollution levels. Researchers found that higher PM2.5 exposure was associated with a greater risk of low birth weight and preeclampsia, a potentially serious pregnancy complication marked by high blood pressure.Corresponding author Prof Subhradip Karmakar from the biochemistry department at AIIMS Delhi said gestational exposure to PM2.5 and PM10 could breach the placental barrier and trigger oxidative stress and inflammation, affecting genes that regulated fetal growth.“We also found evidence of toxic metals such as lead, cadmium and antimony accumulating in placental tissue, suggesting that pollutants can reach the fetus and potentially influence growth and neurodevelopment,” he said.One of the study’s key discoveries was the identification of a gene called IGFBP3, which plays an important role in fetal growth. Researchers found that pollution-related inflammation suppresses this gene, potentially disrupting placental development and healthy fetal growth.The study also found evidence that toxic metals present in polluted air, including lead, cadmium and antimony, can accumulate in placental cells and may be transferred to the fetus. Offspring exposed to pollution during pregnancy showed behavioural and developmental changes after birth in animal experiments.Researchers said the findings provided fresh evidence that air pollution was not only a respiratory and cardiovascular health issue but also a significant threat to maternal and child health. They stressed the need for stronger pollution-control measures.