Plastics, Phthalates & Male Fertility: What You Should Know (Without the Panic)

If you’ve spent any time online lately, you’ve probably seen the headlines warning about plastics, chemicals, and declining sperm counts. A recent New York Times opinion piece even reignited concerns about whether everyday environmental chemicals, especially phthalates, could be quietly affecting male fertility. (If you’re curious, you can read it here: Freeze sperm? Infertility? Chemicals?.)

For individuals and couples building their families with donor sperm, these stories naturally raise questions. Should you be worried? Do phthalates really impact fertility? And what does this mean for choosing a donor?

Let’s walk through the science together!

What Exactly Are Phthalates?

Phthalates are chemical additives used to make plastics soft and flexible. They show up in places you’d expect (like plastic food packaging or vinyl flooring) and places you might not (like fragrances, detergents, cosmetics, and even the coating on certain medications). Because these chemicals aren’t tightly bonded within the plastic, they can gradually migrate into food, air, dust, or onto the skin. In other words, almost everyone is exposed to some degree.

The reason phthalates get so much attention is because they’re considered “endocrine-disrupting chemicals”, meaning they have the potential to interfere with hormonal systems. Since hormones play a critical role in sperm production, researchers have spent years investigating whether phthalates may influence male fertility.

What the Research Really Shows

Over the past decade, declining sperm counts have become a major topic in reproductive health research, and understandably, a source of concern for people trying to conceive.

A landmark 2017 meta-analysis published in Human Reproduction Update analyzed data from more than 40,000 men across decades and found a striking 52% decline in sperm concentration and a 59% decline in total sperm count among men in North America, Europe, Australia, and New Zealand between 1973 and 2011. Follow-up analyses in 2022 and 2023, which included new data from Asia, South America, and Africa, suggest that this decline has continued and may now be occurring globally.

It’s important to highlight that these findings describe population-level trends, not the fertility outlook for any individual man. Even with declining averages, many men have perfectly normal sperm counts.

Researchers also emphasize that declines are likely driven by a combination of contributing factors: lifestyle changes, smoking and alcohol use, stress, chronic illness, heat exposure, and environmental influences such as endocrine-disrupting chemicals like phthalates. The connection isn’t simple or linear, but the global trend is one reason scientists continue investigating these chemicals’ roles in reproductive health.

Some studies link higher phthalate levels with reduced sperm concentration or altered reproductive hormones. A 2023 scientific review highlights that several studies have observed reduced testosterone production and possible disruptions to male reproductive function following phthalate exposure.

And if you’ve seen recent news coverage connecting chemicals to rising infertility, it’s often summarizing this evolving landscape. For example, Scientific American outlined how some environmental chemicals, including phthalates, may have subtle but meaningful effects on fertility in certain populations.

While human studies are mixed, laboratory and animal studies are more dramatic. In research involving mice, high-dose exposure to phthalates like DEHP has been shown to reduce sperm count, increase abnormal sperm, impair sperm motility, and even disrupt the sperm’s ability to fertilize an egg. One detailed study found that phthalate exposure increased oxidative stress, interfered with the acrosome reaction, and compromised overall fertility.

Taken together, the picture is nuanced. Phthalates may contribute to fertility changes for some men, especially at high exposures or vulnerable developmental stages, but they are unlikely to be the primary cause of infertility. Many other factors, such as genetics, lifestyle, smoking, alcohol, medications, health conditions, heat exposure, and additional environmental stressors, play significant roles as well.

What This Means for Donor Sperm

Naturally, patients wonder whether phthalates should influence donor selection. The good news is that donor sperm already undergoes an extremely rigorous screening process that includes medical history, infectious-disease testing, genetic screening, and detailed semen analysis.

Environmental chemical screening, such as measuring phthalate levels, is not part of FDA regulations or donor eligibility standards. This isn’t an oversight; it’s because current human data do not support using phthalate exposure to evaluate or rank donors. Exposure is widespread, highly variable, and nearly impossible to measure accurately on an individual timeline. More importantly, there is no evidence showing that differences in environmental exposure among donors translate into differences in pregnancy outcomes.

For now, donor eligibility is based on factors definitively shown to affect reproductive safety and success. As research evolves, professional guidelines may eventually shift, but the current evidence doesn’t justify screening donors for phthalates.

What You Can Do If You’re Concerned

While it’s impossible to avoid all environmental chemicals, small lifestyle adjustments can meaningfully reduce exposure. Many people choose fragrance-free or phthalate-free personal-care products, use glass or stainless-steel containers when possible, and avoid microwaving food in plastic. Others focus on eating more fresh foods and fewer processed foods. These changes aren’t about achieving perfection; they’re about giving yourself a sense of control in a situation that can otherwise feel overwhelming.

It’s also worth remembering that lifestyle habits, like maintaining a healthy weight, staying active, getting enough sleep, and avoiding smoking, have a far more direct and well-established effect on fertility than phthalate exposure alone. Whether you’re trying to conceive with your own sperm or using donor sperm, these factors matter significantly more.

The Bottom Line: Stay Informed, Not Afraid

Phthalates are part of our modern environment, and yes, scientists are working hard to understand how they might affect human reproduction. But the research so far is neither conclusive nor alarming for donor-sperm recipients. The donor screening process remains thorough, evidence-based, and aligned with current regulations. There is no indication that phthalate exposure differences between donors impact pregnancy success or child health.

If you’d like to discuss environmental chemicals further, your fertility specialist is a great resource. They can help you understand what truly influences fertility and which factors matter most for your unique path.

And as always, our Client Services team is here to help, with compassion, clarity, and evidence-backed information, so you can move forward with confidence on your journey to building your family.