Exposure to “forever chemicals,” or PFAS, during early pregnancy may be connected to future obesity and heart issues, according to a new study published in the Journal of Clinical Endocrinology and Metabolism.

The study tested blood samples from more than 500 women.

All the women were about 10 weeks pregnant when the samples were initially taken, and scientists evaluated the samples for different forever chemicals.

Researchers found that those with higher blood levels of the chemicals both weighed more and had more body fat when they returned for a follow-up visit between 17 to 20 years later.

“If they have a chemistry that allows them to interact with the receptors on a cell surface and if that’s a cell that’s a fat cell, then it might be sending the signal for that cell to take on more fat,” said Nora Demers, an associate professor in the Department of Biological Studies at Florida Gulf Coast University.

PFAS are known to linger in the human body, interfere with hormones and cause a wide range of health problems. Considering the findings, researchers are stressing the need to recognize pregnancy as a sensitive time for chemical exposure that could lead to future heart issues.