The epidermis (skin) is the body’s largest organ, so it would make sense that toxins found in fabrics that sit on the skin’s surface could be absorbed by the skin and make their way into the bloodstream. And polyester has been considered a particularly suspect fabric because it’s made from a chemical called polyethylene terephthalate, a plastic polymer used in various products.
One study published in 1993 followed 24 dogs who were divided into two equal groups, one group wore cotton underpants and the other polyester. At the end of the study period, there was a significant decrease in sperm count and an increase in sperm abnormalities in the dogs who wore the polyester pants. But that said, this study is three decades old, done on dogs, and has had little additional research to show for it since.
So, the jury is certainly still out as to whether fabrics decrease fertility, but there are some things that we do know.
Chemicals Found in Polyester
According to Audrey Gaskins, an associate professor of environmental health at Emory University, most studies are focused on specific chemicals that might be found in fabrics rather than the fabrics themselves, and those chemicals are usually measured in blood or urine.
But fabrics like polyester can contain a number of chemicals that might impact fertility. PFAS, short for per- and polyfluoroalkyl substances, are a group of chemicals found in thousands of products, and they’re difficult for the body to eliminate.
“PFAS are commonly found in water-resistant clothing,” says Gaskins. However, drinking water is likely the most common avenue of exposure, as well as non-stick cookware, and many others.
Research has shown that PFAS can reduce fertility in women by some 40 percent. According to NIH’s National Institute for Environmental Health Sciences, high levels of PFAS found in the blood were linked to a reduced chance of pregnancy and live birth. Other research has shown that PFAS are linked to increased instances of endometriosis and polycystic ovary syndrome (PCOS), both of which reduce fertility.
Read More: How Fast Fashion Harms the Environment — and People's Health
Poor Pregnancy Outcomes
Polyester (when combined with spandex) may also contain bisphenol A (BPA), another chemical compound that has been shown to potentially impact fertility. A December 2022 study published in the Journal of Clinical Medicine found a higher prevalence of PCOS in women with high amounts of BPA in their blood.
Finally, polyester can contain phthalates, a chemical commonly used in things like sports bras and other pieces of clothing. These, too, have been shown to have a negative impact on fertility. A study published in the September 2021 issue of the journal Best Practice & Research Clinical Endocrinology & Metabolism found that higher concentrations of the chemical have been associated with decreased rates of pregnancy, increased incidences of miscarriage, and other pregnancy complications.
“We’ve found suggestive associations between higher concentrations of bisphenol and phthalate metabolites and worse markers of reproductive health like poor success with IVF,” says Gaskins. “What we don’t know is where the source of exposure is coming from.”
Exposure to Fertility-Decreasing Chemicals
Still, the obvious implication if you’re trying to get pregnant is to try to decrease your exposure to any of these chemicals through any route possible, especially when you have control over exposure. If we know there are chemicals in these fabrics, decreasing use of them would be more achievable for many people compared to, say, changing your drinking water, says Gaskins.
There’s definitely no downside to decreasing your exposure to these chemicals, and while clothing is likely not the largest means of exposure to things like PFAs, phthalates, and BPA, if you’re trying to get pregnant, they’re certainly a good place to start.
This article is not offering medical advice and should be used for informational purposes only.
Read More: What Are the Risks of PFAS That Continue to Escalate?
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Urology Research. Effect of different types of textile fabric on spermatogenesis: an experimental study
National Institute of Environmental Health Sciences. PFAS Exposure Linked to Reduced Fertility in Women
Center for Environmental Health. What You Need to Know About BPA in Clothing
Journal of Clinical Medicine. Bisphenol-A and Female Fertility: An Update of Existing Epidemiological Studies
Best Practice & Research Clinical Endocrinology & Metabolism. Phthalates, ovarian function and fertility in adulthood
Sara Novak is a science journalist based in South Carolina. In addition to writing for Discover, her work appears in Scientific American, Popular Science, New Scientist, Sierra Magazine, Astronomy Magazine, and many more. She graduated with a bachelor’s degree in Journalism from the Grady School of Journalism at the University of Georgia. She's also a candidate for a master’s degree in science writing from Johns Hopkins University (expected graduation 2023).
