A new study by researchers at Fudan University and Zhengzhou University in China has revealed the impact of prenatal ozone (O3) exposure on childhood growth and obesity.

Their findings showed that such exposure is associated with accelerated BMI gain or decelerated body length gain and may increase the risk of obesity in children during their early years.

The participants in the study were mothers and child pairs who had lived in Shanghai for more than a year prior to pregnancy. Of the original participants a total of 4,909 went on complete physical development examinations at 1, 2, 4, 6, 9, 12, 18, and 24 months.

The team used a high-resolution model to estimate prenatal ozone exposure based on the home addresses of pregnant women.

Using the World Health Organization’s standards for children’s growth and development the team calculated each child’s BMI for age Z score (BAZ), weight for age Z score (WAZ), weight for length Z score (WLZ), and length for age Z score (LAZ), where Z is the deviation from the average.

It was found that for every 10 μg/m³ increase in concentration of ozone during pregnancy the Z scores for BMI, weight-for-age, and weight-for-length rose significantly.

For the total population, an increase of 10 μg/m³ in O3 concentration was linked to a 1.239-fold increase in accelerated growth in the BMI for age Z score, whereas the likelihood of an increase in the length for age Z score decreased. 

While the mechanisms through which which prenatal O3 exposure contributes to childhood obesity are unclear, the team point to recent studies which have shown that these mechanisms ‘may be related to placental epigenetic regulation, lipid metabolism, inflammation, or oxidative stress.’

Dr. Yunhui Zhang from School of Public Health at Fudan University, a corresponding author of the study, stated, ‘Our research highlights the significant impact of prenatal ozone exposure on early childhood growth and obesity. These findings underscore the importance of addressing air quality issues to protect the health and development of future generations.’