Air pollution may be doing more damage during pregnancy than previously understood. A new study by researchers at All India Institute of Medical Sciences (AIIMS Delhi) has found that exposure to polluted air can damage the placenta, restrict fetal growth and increase the risk of pregnancy complications.
The research suggests that fine particulate matter, commonly known as PM2. 5 and PM10, may even affect a child’s development after birth.
What the Study Found
Published in the journal EMBO Molecular Medicine, the study examined the impact of urban air pollution using laboratory experiments, animal models and data from human pregnancies.Researchers discovered that tiny pollution particles can cross the placental barrier, triggering inflammation and oxidative stress. This process can interfere with the placenta’s ability to deliver oxygen and nutrients to the developing fetus.
The team found that exposure to particulate matter affected several key placental functions, including blood vessel formation, nutrient transport and healthy fetal growth.
As a result, babies may face a higher risk of growth restrictions before birth.
Higher Risk of Low Birth Weight and Pregnancy Complications
The researchers also analysed data from 994 pregnancies across regions with varying pollution levels. These findings reinforce concerns that long-term exposure to polluted air can affect both maternal and fetal health.Their findings showed that increased exposure to PM2. 5 was linked to a greater likelihood of:
Low birth weight
Preeclampsia, a serious pregnancy complication marked by high blood pressure
Toxic Metals Found in Placental Tissue
Corresponding author Subhradip Karmakar said the study revealed that pollution particles could breach the placental barrier and influence genes responsible for 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.
According to the researchers, the presence of these metals raises concerns about the long-term health effects of prenatal pollution exposure.
Scientists Identify Key Gene Affected by Pollution
One of the most significant discoveries involved a gene called IGFBP3, which plays a crucial role in fetal development. Researchers found that inflammation caused by air pollution can suppress this gene, potentially disrupting placental development and affecting healthy fetal growth.
The study suggests that this mechanism may help explain why pollution exposure is associated with poorer birth outcomes.
Animal Studies Show Developmental Changes
The team also conducted experiments on pregnant rats exposed to urban particulate matter. The results were striking:Smaller litter sizes
Abnormal placental development
Reduced birth weight
Slower growth in offspring
Researchers further observed behavioural and developmental changes in offspring after birth, indicating that the effects of prenatal pollution exposure may extend beyond pregnancy.
More Than a Respiratory Health Problem
The findings add to growing evidence that air pollution is not only linked to respiratory and cardiovascular diseases but may also pose serious risks to maternal and child health.
Researchers said the study highlights the urgent need for stronger pollution-control measures, particularly in urban areas where pregnant women are routinely exposed to high levels of particulate matter.
As cities continue to grapple with worsening air quality, the research underscores a critical message: cleaner air may be essential not just for current health, but for the well-being of future generations.

