Infertility in Men: Are His Swimmers Stuck?
A growing number of men have bad sperm, and experts say many of the reasons are preventable
Men like to boast about their virility, but many don't think about how to protect their baby-making power. They just assume that when the time comes, they'll step up to the plate and hit a home run with their bat. Big mistake. According to new research, one in five guys ages 18 to 25 is "subfertile," and fertility rates among men of all ages have been dropping steadily for the past 60 years. So what qualifies as male subfertility, exactly?
His testes produce too few sperm. (Fifteen to 20 million sperm per milliliter of semen is considered normal.)
A big percentage of his boys move slowly or not at all.
A bunch of his sperm are misshapen. For maximum fertility, more than 4 percent of sperm at any given time should be physically perfect.
Modern-Day Dilemma
"Many of the things that make our lives easier may be affecting sperm production and vitality," says urologist Jeanne O'Brien, M.D., of the University of Rochester Medical Center. Chemicals like phthalates (used to make plastic items durable), parabens (the preservatives in grooming products), and pesticides can interfere with sperm, leaving a man with too few or a whole lot of damaged ones. Certain UV filters in sunscreens, as well as additives fed to livestock, can also curb a guy's fertility. "Even birth-control pills may be having an effect," says Marc Goldstein, M.D., surgeon-in-chief at the Cornell Institute for Reproductive Medicine. Most filters can't catch the Pill hormones that women pee out, allowing them to seep back into the water supply.
The majority of the above chemicals are endocrine disrupters, or xenoestrogens, substances that mimic the female sex hormone estrogen and interfere with a body's normal balance of androgens, the messengers between the brain and the reproductive system. Normally, a man has small amounts of estrogen in his body, but too much of the stuff can kill sperm cells. (Most of these chemicals aren't great for women either, but men are particularly sensitive to too much estrogen.)
Sadly, some of the havoc wreaked by xenoestrogens can take place even before a man is born. Exposure in utero to phthalates, pesticides, and preservatives may lead to a lower sperm count, says O'Brien. What's more, studies show that fetus testicles exposed to endocrine disrupters can develop abnormally, a growing problem known as testicular dysgenesis syndrome (TDS). Because it causes defects in a man's reproductive tract, TDS has been linked to testicular cancer and, you guessed it, subfertility. It's one reason so many men are experiencing issues at such a young age.
The Party in His Pants
Acting like a cast member of The Hangover may seem fun, but smoking (cigarettes or pot) and excessive drinking are tantamount to spermicide. "The active ingredient in marijuana binds to estrogen receptors in the testicles," says Goldstein. As a result, pot smokers often have defective sperm that can't hang on to an egg long enough to fertilize it. (While occasional tokers compromise their short-term fertility, long-term partyers may become permanently subfertile.) Similarly, booze puts the kibosh on the body's absorption of zinc, a mineral needed to form strong sperm.
Another way a dude may decrease his potency? By heating things up. "There is a reason the testicles hang outside the body," says Goldstein. "They need to maintain a slightly lower temperature in order to manufacture sperm." Frequent hot-tub or sauna sessions can crank up scrotal temperatures and interfere with sperm production. And early research shows that if a guy keeps his cell phone in his front pocket, or props a laptop or iPad on his lap, he could be raising his testicular temperature by more than two degrees. Some doctors go so far as to suggest that patients switch from tighty-whities to boxers and avoid crossing their legs in order to keep their coconuts cool, though no studies prove either is a big risk.
Packing on excessive body fat has also been linked to elevated estrogen levels, and, therefore, to subfertility. (Doctors say it's best for men to maintain a BMI of 30 or under.) Stress, too, may cancel out the hormones that help a man produce healthy sperm.
But while experts continue to study the particulars, there is ample evidence that lifestyle adjustments can help a guy score physically perfect swimmers, says David Tourgeman, M.D., a fertility physician in Los Angeles. And male subfertility is often reversible, sometimes in as few as three months. "The life cycle of sperm is 54 to 72 days," says O'Brien, "so if a man stops sperm-damaging behavior, he has a good chance of turning things around."