People planning a pregnancy might wonder about the health of their sperm. Know what can affect male fertility — then consider steps to help the sperm achieve the goal.

Various medical issues can contribute to male fertility problems, including:

• A problem in the hypothalamus or the pituitary gland — parts of the brain that signal the testicles to produce testosterone and sperm (secondary hypogonadism)
• Testicular disease
• Sperm transport disorders

Age also can play a role. The ability of sperm to move and the number of typical sperm tend to decrease with age, affecting fertility, especially after age 50.

Simple steps to increase the chances of producing healthy sperm include:

• Maintain a healthy weight. Some research suggests that increasing body mass index (BMI) is linked with decreasing sperm count and sperm movement.
• Eat a healthy diet. Choose plenty of fruits and vegetables, which are rich in antioxidants — and might help improve sperm health.
• Prevent sexually transmitted infections (STIs). Sexually transmitted infections — such as chlamydia and gonorrhea — can cause infertility in men. Limiting the number of sexual partners and always using a condom for sex — or staying in a mutually monogamous relationship with a partner who isn't infected — can help protect against STIs.
• Manage stress. Stress can decrease sexual function and interfere with the hormones needed to produce sperm.
• Get moving. Moderate physical activity can increase levels of powerful antioxidant enzymes, which can help protect sperm.

Sperm can be especially vulnerable to environmental factors, such as exposure to excessive heat or toxic chemicals. To protect fertility:

• Don't smoke. Men who smoke cigarettes are more likely to have low sperm counts. If you smoke, ask your doctor to help you quit.
• Limit alcohol. Heavy drinking can lead to reduced testosterone production, impotence and decreased sperm production. If you choose to drink, do so in moderation. For healthy adults, that means up to one drink a day for women and two drinks a day for men.
• Avoid lubricants during sex. While further research is needed on the effects of lubricants on fertility, consider avoiding lubricants during intercourse. If necessary, consider using mineral oil, canola oil, mustard oil or a fertility-friendly lubricant, such as Pre-Seed.
• Talk to a health care provider about medications. Calcium channel blockers, tricyclic antidepressants, anti-androgens, opioids and other medications can contribute to fertility issues. Anabolic steroids and other illicit drugs can have the same effect.
• Watch out for toxins. Exposure to pesticides, lead and other toxins can affect sperm quantity and quality. If you must work with toxins, do so safely. For example, wear protective clothing, use protective equipment, such as safety goggles, and avoid skin contact with chemicals.
• Stay cool. Increased scrotal temperature can hamper sperm production. Although the benefits have not been fully proved, wearing loose-fitting underwear, reducing sitting, avoiding saunas and hot tubs, and limiting scrotum exposure to warm objects, such as a laptop, might enhance sperm quality.

Chemotherapy and radiation therapy for cancer can impair sperm production and cause infertility that might be permanent. Ask a health care provider about the possibility of retrieving and storing sperm before treatment.

Adopting healthy lifestyle practices to promote fertility — and avoiding things that can damage it — can improve the chances of conceiving. If you and your partner haven't gotten pregnant after a year of unprotected sex, however, you might consider being evaluated for infertility. A fertility specialist might be able to identify the cause of the problem and provide treatments that place you and your partner on the road to parenthood.