The chemical BPA can be found in plastics around the world. Now scientists have linked the environmental pollutant as a contributing factor in preterm births.

"Women are continuously exposed to BPA because it's used in the construction and coatings of food containers and its release into food is increased by microwave or other heat sources," said Ramkumar Menon of the University of Texas Medical Branch. "In fact, BPA is so widely used that nearly all women have some level of exposure."

BPA, or Bisphenol A, is structurally similar to the female hormone estrogen. This means that it can bind to estrogen receptors within the body, including those responsible for inflammation. If a woman experiences abnormal inflammation, her risk of pregnancy complications can increase. These complications can also include water breaking early and preterm birth.

BPA can be found in plastic water bottles, plastic containers, and even in plastic that's used around the home in furniture, dishware and other items. While BPA is largely being phased out over time by companies, including Wal-Mart, there is still BPA that can be found in many different products.

In this latest study, the researchers analyzed blood samples from pregnant women when they were admitted to the hospital for labor and for delivery. The researchers also looked at the amniotic fluid of the fetus that was collected during labor. In the end, they found that women with elevated levels of BPA in their blood were more likely to deliver their babies early compared with women with lower levels of BPA.

"Widespread use of BPA in materials of our daily life and our findings that all patients have some level of exposure suggests that contact with these materials is unavoidable," Menon said. "This suggests that a better understanding of how BPA may alter maternal physiology is needed to minimize the risk of adverse pregnancy outcomes."

The findings show that BPA may have more adverse health effects than first expected. While other studies have shown that BPA may impact growth in the past, this is the first time it's been looked at in regards to delivery and birth.

The findings are published in the March 2016 journal The Journal of Maternal Fetal & Neonatal Medicine.