Plastic and Parenthood: Are Microplastics Threatening Fertility?

alarms about its potential effects on fertility, especially in countries like Japan where birth rates are already in steep decline.

 

The Italian study, published in Ecotoxicology and Environmental Safety, labelled microplastics an “emerging threat to female fertility” and called for urgent investigation into their reproductive impact. The findings add to mounting global evidence that plastic particles — once considered inert — are not only polluting our oceans but may now be interfering with our bodies at the cellular level.

A Global Plastic Problem, A Personal Health Risk

Microplastics, defined as plastic particles under 5mm in diameter, and even smaller nanoplastics, are now found almost everywhere — in our food, water, and even the air we breathe. They originate from packaging, clothing, and plastic waste that breaks down over time, eventually making its way into marine life, food chains, and, ultimately, us.

While the physical presence of microplastics in the body is troubling enough, scientists believe it’s the chemical additives in plastics that pose the greatest threat. Plastics often contain endocrine-disrupting chemicals — substances that mimic or interfere with hormones. These include phthalates, bisphenol A, and PFAS, or “forever chemicals,” all linked to hormonal imbalances, reproductive issues, and even cancer.

“Many of these chemicals resemble female hormones and bind to hormone receptors, sending confusing signals in the body,” explains Professor Hideshige Takada, a leading expert in microplastic research at Tokyo University of Agriculture and Technology. “We now know they can impact fertility, brain development, and sexual function.”

Fertility in Japan Under Pressure

Japan is already facing a demographic crisis, with an ageing population and declining birth rate. Fertility concerns are on the rise: in 2021, one in every 4.4 couples had sought testing or treatment for conception issues — nearly double the rate in 2002.

 

Could microplastics be a contributing factor?

 

Researchers remain cautious. The Italian study, for instance, found microplastics in 14 out of 18 women — a small sample size. Critics also point out the risk of contamination during sample collection and the difficulty in distinguishing plastics from other chemical compounds naturally present in the body. A commentary published in Nature recently called for more rigorous standards and transparency in microplastics research.

Yet despite these uncertainties, Takada and others argue that the chemical complexity of plastic pollution makes it impossible to dismiss its potential reproductive risks. “We’re not dealing with one substance, but thousands,” Takada says. “Each might seem harmless on its own, but combined, their impact can be far more dangerous.”

 

Beyond Women: What About Male Fertility?

While much attention is focused on female reproductive health, male infertility is also a growing concern. Declining sperm counts, poor motility, and abnormal morphology have been widely documented. However, according to Dr Soichiro Ogawa, a urology professor at Fukushima Medical University, links between microplastics and male infertility remain speculative. “There is not yet enough robust evidence to draw conclusions,” he says, adding that lifestyle factors like smoking still pose far greater risks.

Policy Lagging Behind Pollution

On the policy front, Japan has faced criticism for its reliance on plastic recycling rather than reduction. While 87% of the country’s plastic waste is “recycled,” more than two-thirds of it is incinerated in so-called thermal recycling — a process that releases carbon dioxide and contributes to climate change.

 

Other nations are taking a more proactive stance. In Europe, policymakers use behavioural economics “nudges” to steer consumers and companies away from plastics, often without legislation. Japan’s 2020 plastic bag fee helped reduce usage by half within two years, but single-use plastics like containers, bottles, and utensils remain widespread.

 

Efforts to secure a global plastics treaty stalled at the UN’s recent INC-5 session, though negotiations will resume later this year. Environmental law experts argue that reducing production and consumption — not just improving recycling — is essential to addressing the problem at its root.

What Can Individuals Do?

Takada suggests simple but impactful steps: avoid reheating food in plastic containers, use glass for storage, and limit consumption of bottled water. “These chemicals don’t stay in the body forever. Reducing your daily exposure can reduce long-term risks,” he says.

As the scientific community pushes for better research and stronger regulations, one thing is clear — our plastic habits may be quietly reshaping our reproductive futures. And while definitive answers are still unfolding, the evidence so far suggests caution is not only wise, but necessary.

 

Reference: https://www.theguardian.com/society/2025/apr/19/microplastics-human-ovary-follicular-fluid