Polyester And Fertility: How Your Workout Clothes Might Be Sabotaging Your Reproductive Health

We can’t escape plastic. It’s in our sports bras, leggings, Tupperware, feminine products, and to-go coffee cups. Despite how harmless plastic may seem, Big Plastic doesn’t want you to know that it may negatively affect your fertility. Polyester and Fertility Polyester’s full name is polyethylene terephthalate (PET). Unlike cotton or silk, it is manmade and a petroleum-based synthetic fiber. It’s cheap (well, unless you’re buying Alo), durable, and moisture-wicking, but polyester might come with an unexpected price tag: reproductive health. Research suggests that polyester, especially when worn close to the body, could be interfering with fertility. A study published in 2008 observed female dogs wearing different types of fabric for 12 months. Those dressed in polyester-containing materials showed reduced progesterone levels and failed to conceive. Five months after removing the polyester garments, their hormone levels normalized, and they were able to conceive again. Scientists believe electrostatic fields generated by polyester may disrupt ovarian function, leading to anovulation. Male reproductive health is also in question. Another study followed 24 male dogs over 24 months—half wore polyester underpants, while the other half wore cotton. The polyester group saw a significant drop in sperm count and an increase in abnormal sperm. Even after the polyester was removed, some dogs never recovered their fertility completely. If polyester can do this to dogs, what’s it doing to us? The Plastic We Wear (and Breathe and Eat) Even if you’re not worried about fertility, polyester isn’t doing you any favors . It sheds microscopic plastic particles called microplastics. Every time you wash, wear, or even sweat in polyester, tiny plastic fibers break off and make their way into the environment. AP Environmental student Dylan Selby puts it bluntly: “Polyester breaks down into microplastics, and those microplastics accumulate in organisms up the food chain, ending at humans.” Microplastics have been linked to oxidative stress, hormonal imbalances, and even cardiovascular issues. Most athletic wear, bedding, and even “satin” fabrics are made from it, but don’t fret! Small swaps can make a difference. Make sure to check labels on clothing. If it says polyester, acrylic, or nylon, it’s plastic. Look for cotton, wool, bamboo, or silk instead. Your goal should be to choose natural material, including organic cotton, linen, and bamboo. Yes, they’re more expensive, but they’re comfortable and don’t release microplastics. Invest in quality! Fast fashion loves polyester because it’s cheap and disposable. Buying fewer, higher-quality pieces reduces demand for synthetic fabrics. It’s easy to brush off concerns about polyester since we’ve been wearing it for decades. But if research continues to connect it to fertility issues, microplastic exposure, and hormone disruption, it might be time to rethink our wardrobe choices. Convenience is great, but at what cost? Subscribe today to get unlimited access to all of Evie’s premium content.