Sperm Counts Are On A Rapid Global Decline—Here’s What To Know

It may not be top of mind, but sperm count is something everyone should know about, especially if they’re planning to start a family at some point in their lives. Why? To start, sperm count is a key factor in male fertility. Despite the widespread misconception that a couple’s fertility is mainly a measure of the woman’s reproductive capacity, men’s overall and reproductive health is solely responsible for 20 percent of all infertility cases and contributes to 50 percent of all instances of infertility.  

Furthermore, multiple studies suggest that sperm count is on a rapid global decline. One 2017 study published in Human Reproduction Update reported a significant decline in sperm counts between 1973 and 2011. A 2022 review, meanwhile, found that men’s sperm counts have decreased by a whopping 62 percent in the last 50 years. 

Despite all this, sperm count—and more specifically, its role in fertility—is something most men know very little about. Ahead, learn why sperm count levels are dropping, plus things men can do to support healthy sperm. 

• ABOUT OUR EXPERTS: Lisa Golding-Granado, M.D., is a board-certified internal medicine specialist focused on hormone health and medical director of Serotonin Centers of Colts Neck, NJ. Gowri Reddy Rocco M.D., M.S., is a board-certified family medicine and regenerative anti-aging medication specialist committed to helping men preserve fertility, sexual function, and hormone health as they age.

Sperm Count, Explained 

“Sperm count measures the amount of sperm in a semen sample,” explains Lisa Golding-Granado, M.D., a board-certified internal medicine specialist focused on hormone health and medical director of Serotonin Centers of Colts Neck, NJ. (ICYMI: Sperm are the reproductive cells created by the testicles, while semen is the sperm-transporting fluid secreted during ejaculation that also contains water, mucus, and plasma.)

When someone has a low sperm count, it means the number of sperm per milliliter of semen or the number of sperm per ejaculatory load is low. Medically speaking, having fewer than 10 million sperm per milliliter of semen or fewer than 39 million sperm per load is considered lower than normal. 

Since sperm cannot be seen by the naked eye, individuals cannot assess sperm counts on their own. Instead, sperm count is assessed as part of a larger test called semen analysis, says board-certified family medicine and regenerative anti-aging medication specialist Gowri Reddy Rocco M.D., M.S., an expert committed to helping men preserve fertility, sexual function, and hormone health as they age. Performed in a medical setting, semen analysis tests look at the sperm count, as well as sperm shape, motility, and the acidity (or pH) of an ejaculatory sample, he says. 

The Main Cause of Low Sperm Counts 

If you’re in the business of finger-pointing, aim your weapon at environmental toxins. “More standardized research is needed to establish a definitive link, but much of the current research posits pollution and environmental factors as the enemies leading the charge of declining sperm counts,” says Golding-Granado.

One 2022 review published in the Environmental Sciences Europe journal found that the level of air pollution was significantly associated with decreased semen volume, sperm concentration, and reduced sperm motility. These findings align with other research, which suggests that male sperm counts are lower in urban areas, where air pollution is higher, than in more rural locations. 

Read More: These Food And Drink Habits Can Lower Your Testosterone

The chemicals in the air aren’t the only ones that may play a role in lower sperm count—those in our household items do, too. The main toxins implicated include endocrine (hormone) disruptors, such as phthalates, Bisphenol A (BPA), pesticides, and herbicides, says Golding-Granado. Indeed, phthalates, which are found in plastics, cosmetics, and household products, have been shown to negatively impact sperm quality by disrupting hormones, she says, as have the pesticides and herbicides used to treat produce. Meanwhile, BPA has been linked with lower sperm concentrations, due to the negative effect it has on male reproductive organs. 

Notably, climate change may also negatively affect sperm count. A 2022 review published in the Iranian Journal of Public Health found that high ambient temperatures harmed sperm count, motility, and shape. 

Other Factors That Impact Male Sperm Count

Environmental toxins aren’t the only cause of tanking low sperm counts, though. The researchers behind one Current Opinions in Urology study say that increased rates of obesity and poor diet are also to blame. In fact, one study found that obese men are 42 percent more likely to have a low sperm count than their normal-weight peers and 81 percent more likely to produce no sperm at all. Meanwhile, the increase of processed, sugar-laden foods (which has been rising for the last decade) also negatively affects sperm count through its effect on overall health, adds Golding-Granado. 

“Lack of physical exercise, increased alcohol use, and increased use of over-the-counter and prescription drugs all contribute, too,” says Rocco. Indeed, research has shown that alcohol disrupts sperm production by decreasing testosterone production and even contributing to testicular atrophy, and that recreational drugs interfere with the endocrine system and ultimately impact free-floating testosterone levels.  

Getting Sperm Count Assessed

On a global level, the sperm count freefall is cause for concern because it suggests that the Earth itself—and the people inhabiting it—are getting less and less healthy. On an individual level, “having a lower sperm count means reduced fertility, and makes it harder to conceive naturally,” says Rocco. 

For those concerned with their future reproductive capabilities or simply wanting to better understand their overall health, sperm count data is good to know. As it goes, a lower sperm count can tip an individual off on an underlying health issue. Hormone disorders (like low testosterone), exposure to poison and radiation, untreated infections, and nutritional deficiencies, for example, can all cause a lower sperm count, Rocco says. 

If you’re looking to start a family soon or want to better understand your or your partner’s sperm status, a male fertility specialist (like an endocrinologist) can order a comprehensive male fertility assessment, suggests Golding-Granado. Usually, this assessment includes a semen analysis and sometimes even hormone and genetic testing. These experts can also help people explore family-planning options in the event that low sperm count or other infertility issues are determined, she explains.  

How To Protect Sperm Count 

No doubt, understanding the reality of globally declining sperm counts and their environmental causes can be overwhelming—especially if you’ve always wanted to be a parent. The good news is that there are ways to support overall sperm count and fertility. Just be mindful that “supporting fertility has to be a life-long process, not just a short-term effort,” says Golding-Granado.

Broadly speaking, the best way to protect sperm count is by adopting healthier habits overall. To start, Golding-Granado suggests that “eating a healthier diet replete with plenty of fruits, vegetables, whole grains, probiotics, and lean proteins can support sperm production.” One 2023 study published in Current Nutrition Reports linked a Mediterranean diet—an eating plan that bases meals on fruits, veggies, herbs, and healthy fats—with a higher sperm count and semen quality than other eating plans. Notably, a Mediterranean diet is also low in processed foods and booze, which Golding-Granado suggests limiting in the name of sperm health. “Trans fats, excessive sugar, and alcohol all impair sperm quality,” she says.  

Whether your plate isn’t always bursting with bright, colorful foods or you simply want to do your due diligence in supporting healthy sperm, you might consider adding a daily supplement or two to your routine. For starters, Rocco recommends taking a daily multivitamin. Otherwise, ensure you’re stocked on zinc, vitamin C, and omega-3 fatty acids, all of which promote sperm health via their antioxidant properties. 

Maintaining a regular exercise routine can also support sperm count by promoting a healthy weight and body composition, thus reducing the risk of obesity. Indeed, one 2023 study published in The World Journal of Men’s Health found a link between regular low- and intermediate-intensity exercise and higher sperm counts, while another study found that men who reported exercising had greater sperm count and motility than those who reported exercising less. 

Finally, Rocco advises managing stress levels and logging quality sleep. Both of these, he says, will help any individual maintain a healthy endocrine system, which ultimately supports sound sperm count.