BPA (or bisphenol A), the chemical found in certain types of food packaging products, may be linked with an increased risk of miscarriage, according to a new study conducted at Stanford University Medical Center. During the study, a team of researchers led by obstetrics and gynecology professor Dr. Ruth Lathi gathered blood samples from 114 women. All of the women were between four and five weeks pregnant at the time the samples were collected.

The researchers then measured the amount of BPA in the samples taken from women who went on to give birth, as well as those who experienced a miscarriage. The subjects in the study with the lowest levels of BPA in their blood were about 80% less likely to have a miscarriage than women with the highest levels of BPA.

How Does BPA Enter the Body?

As mentioned, BPA is found in food packaging products such as cans and certain plastic containers. However, it’s also found in other products ranging from credit card receipts to dental sealants. The majority of individuals have at least trace amounts of BPA in their urine, indicating that BPA is able to transfer from the packaging or product to the food and ultimately to the person’s body. BPA molecules are quite similar to estrogen molecules, leading some to believe that BPA exposure may interfere with hormone signaling.

As for the specific reason behind the link between miscarriage risk and BPA, researchers simply aren’t sure. Hormone signaling may have something to do with it, but the researchers think chromosomes may be involved as well. In conducting their study, they examined the chromosomes of the miscarried fetuses and found that some had genetic abnormalities, while others did not.

Staying Away from BPA

One of the limitations of the study was the fact that BPA is quickly eliminated from the body. As such, a person’s measured BPA level could vary greatly depending on the day when the blood sample is taken and how much BPA they’ve been exposed to recently. Still, BPA can build up in the body over time and potentially lead to health problems, so it’s definitely worthwhile to avoid it when you can. Here are some ways to do that:

• Stay away from plastic containers that display 3, 6 or 7 as recycling codes, as these may contain BPA. Especially avoid reusable plastic containers with these specific markings.
• Keep plastic containers out of the sun. Exposure to sunlight may cause them to release more BPA.
• Minimize your consumption of canned foods, as these almost always contain BPA.
• Don’t microwave foods in plastic containers. Glass cookware is an inert, safe option.

More Research on BPA

The new study adds to existing evidence suggesting a link between BPA and pregnancy issues. One previous study indicated that monkeys exposed to high levels of BPA have a greater risk of their eggs developing abnormally, while another recent study showed a reduction in the number of harvestable eggs among women with high BPA levels during in vitro fertilization.

Still, Dr. Lathi said that plenty of women with measurable levels of BPA in their blood have perfectly healthy babies, and that avoiding BPA entirely is almost impossible.

Dr. Lathi also said that the study found a link of association between miscarriage and high levels of BPA, though it does not prove that BPA exposure directly causes miscarriage. She suggested that a future study should determine whether actively reducing exposure to BPA results in a lowered risk of miscarriage.

The Bottom Line

Women may be significantly more likely to experience a miscarriage if their blood contains high levels of BPA, which can be found in many packaged foods and other products, according to a recent study.

The study will be presented at the upcoming annual joint meeting of the American Society for Reproductive Medicine and the International Federation of Fertility Societies.