Male Fertility Decline Raises Questions About Causes and Severity

Scientists and physicians have reached consensus on a troubling trend: male fertility is declining globally. However, the exact causes behind this phenomenon remain elusive, with experts describing a complex web of potential factors rather than a single culprit.

At Columbia University Fertility Center in New York, Dr. Alex Robles confirms what many specialists are seeing. “We’re certainly seeing more couples where the male factor contributes to infertility,” he told Fox News Digital. “At least one-third of couples we evaluate have some male component.”

The data behind this trend appears compelling. A landmark meta-analysis published in Oxford Journals: Human Reproduction Update found that sperm counts in Western countries have declined by almost 60% globally since 1973. A 2023 update to this research confirmed these alarming results.

Lead study author Hagai Levine, a public health physician at the Hebrew University-Hadassah Braun School of Public Health, describes the situation as “the canary in the coal mine,” warning that this trend could ultimately threaten human reproduction if not addressed.

“It signifies that something is very wrong with our current environment, as lower sperm counts predict morbidity and mortality,” Levine told National Geographic.

However, not all research supports these conclusions. A 2025 Cleveland Clinic analysis examining studies from the past 53 years found sperm counts to be relatively steady. Scott Lundy, a reproductive urologist at Cleveland Clinic and primary author of that study, offers a more tempered view.

“There is no evidence to suggest that this decline is the cause of a precipitous decline in the ability to cause pregnancies,” Lundy explained. “Most men, even with a modest decline in sperm counts, will still have no issues conceiving.”

Multiple Factors at Play

Experts point to numerous lifestyle and environmental factors that may contribute to declining fertility rates. Dr. Robles notes that obesity, smoking, diet quality, environmental exposures, and delayed parenthood all play roles in the overall trend.

Substance use appears to be a significant factor. Heavy drinking and marijuana consumption directly contribute to declining fertility, according to research cited by National Geographic. The good news is that quitting these habits, along with exercise and weight management, can help improve fertility outcomes.

Health status also plays a crucial role. “Systemic inflammation, infection, and disease can have a big, profound effect on the current status of fertility,” explains Lundy. Men recovering from fevers caused by infections like flu or COVID-19 typically experience “drastically lower” sperm counts for up to three months afterward.

Allan Pacey, deputy dean of the Faculty of Biology, Medicine and Health at the University of Manchester, suggests demographic factors may also contribute to the perceived decline. Increased contraception use, men choosing to delay fatherhood, or opting not to have children could all influence fertility statistics.

Environmental chemicals present another area of concern. While the effects of microplastics remain unclear, there is evidence that endocrine-disrupting chemicals found in reusable plastics and disposable products may alter male fertility.

Debunking Common Myths

Social media has fueled numerous myths about male fertility that lack scientific backing. One common claim suggests keeping cellphones in front pockets harms sperm production. While Lundy acknowledges such an effect is biologically possible, current scientific evidence doesn’t support this concern.

Another widespread misconception is that infertility primarily affects women. In reality, male factors contribute to approximately one-third to one-half of all infertility cases, according to Robles.

The effectiveness of supplements for boosting sperm counts represents another area where marketing often outpaces science. “Men should focus on factors that we know matter: maintaining a healthy weight, avoiding tobacco, limiting alcohol and managing chronic health conditions,” Robles advises.

For those concerned about fertility issues, experts recommend consulting with a urologist rather than relying on internet advice. A comprehensive evaluation typically includes semen analysis, hormonal testing and medical history review, alongside lifestyle assessment.

Modern fertility centers increasingly incorporate advanced technologies, including AI and robotics, to expand treatment options. “Technologies like this are expanding options for patients who previously had very limited paths to biological parenthood,” notes Robles.

As research continues, the message from experts remains clear: male fertility involves complex interactions between lifestyle, environment and health, requiring individualized assessment rather than one-size-fits-all explanations.