Nearly half of all fertility troubles are linked to sperm problems. Here are tips for their proper care and feeding.
Think "fertility problem," and most people assume there's something wrong with the female half of the conception equation. In fact, when couples are having trouble making a baby, what's known as "male factor" is responsible an estimated 40 percent of the time. Here's what a guy can do—and what he should avoid doing—to maximize his chances of making plenty of hardy, healthy, fast-swimming sperm.
Eat Oranges, Not Cheetos: Eating fruits, vegetables, whole grains and low-fat protein helps prevent a man from coming up short on the nutrients necessary for making top-notch sperm; vitamins C and E, zinc and folic acid are particularly important. Over-the-counter supplements such as FertilAid for Men and FertilityBlend for Men, which contain sperm-friendly vitamins and minerals, are safe to take and may help, but there's no proof they boost pregnancy rates.
Review His Medications: Certain drugs, including steroids and those that treat high blood pressure, ulcers, hair loss and depression, may impair a man's ability to father a child. Every medication he takes—over-the-counter as well as prescription—should be checked with his doctor or pharmacist for possible effects on fertility.
Kick Some Butts: Smoking cigarettes creates free radicals that cause cell damage, lowering sperm count and diminishing sperm quality. Dad's smoking habit may also increase his future children's chances of developing leukemia and lymphoma.
Moderate the Mountain Biking: If a man logs a lot of miles mountain biking, he can incur testicular damage that reduces his ability to father a child. Stopping frequently to rest, wearing padded bike shorts and using a padded seat reduce the chance of problems, even if he's a road biker.
Get a Move On: If he's over 30, you may want to get started on the baby-making process. One study of healthy nonsmokers found that 50-year-old men made 20 percent less sperm than 30-year-olds. The researchers estimate that sperm volume and motility (movement) decrease by about 5 percent each year after age 30.
Overuse the Cellphone: Men who talked on cellphones for more than four hours a day produced only 75 percent as many sperm as those who did not use the devices, a 2006 Cleveland Clinic study found. They also had lower-quality sperm, including slower swimmers. Note: The researchers did not ask men about their diet or lifestyle, so the results of this study are not conclusive.
Get Chubby: In a Danish study of nearly 1,600 men, those who were overweight made significantly less sperm. In addition to having higher sperm counts, men in the normal-weight range—a body mass index (BMI) of 20 to 25—also had a lower percentage of abnormal sperm.
Expose Himself: A prospective dad needs to take care with chemicals, especially if he's a painter, printer, firefighter, agricultural worker or janitor. (A review of 10 years of studies linked these occupations to birth defects.) He should check if his workplace provides proper protection and ventilation.
Do Recreational Drugs: Smoking marijuana turns sperm into hyperswimmers that "burn out" before they're able to make their way to the egg. Cocaine may actually adhere to sperm without hampering its ability to fertilize an egg, increasing the chances that a child may be affected by the father's drug use.
Drink Too Much: Heavy drinking is linked with decreased sperm formation and function. While the precise link between moderate drinking and fertility in men is murky, a prospective father should play it safe by limiting alcoholic beverages to two a day, max.
Too Darn Hot: Sperm thrive at normal body temperature. Wearing tight briefs hikes the heat in the scrotum, possibly suppressing sperm production (though this isn't proven). Laptop computers may do the same: A study at the State University of New York at Stony Brook looked at 29 healthy men ages 21 to 35 and found that balancing computers on their laps for an hour increased scrotal temperature about 5* F.
For everything you need to know to maximize your chances of conceiving, visit our Getting Pregnant feature.