Study shows that thyroid-altering BPA may also contribute to premature births

A recent study conducted in Mexico City suggests that low level Bisphenol A (BPA) exposure may impact placental tissue development and thyroid function in humans. The presence of BPA has been documented worldwide in a variety of human biological samples.

The aim of the study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, and relate the concentrations to the risk of premature birth.

A total of 60 participants in the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) study were selected based on whether their child's birth was premature. Third trimester urine samples were analyzed.

The findings show that BPA was detected in 80 percent of the urine samples. This is the first study to document measurable levels of BPA in the urine of a population of Mexican women.

This study also provides preliminary evidence based on a single spot urine sample collected during the third trimester that pregnant women who delivered prematurely had higher urinary concentrations of BPA compared to women delivering after 37 weeks.