Healthy sperm aren't always a given. Understand how lifestyle factors can affect your sperm and what you can do to improve your fertility.
By Mayo Clinic staffDo your sperm pass muster? If you and your partner are planning a pregnancy, you may be wondering about the health of your sperm. Start by understanding the various factors that can affect male fertility — then consider steps you can take to help your sperm become top performers.
What determines sperm health?
Sperm health depends on several factors, including:
- Quantity. You're most likely to be fertile if your ejaculate — the semen discharged in a single ejaculation — contains more than 39 million sperm.
- Quality. You're most likely to be fertile if more than 4 percent of your sperm have a normal shape and structure. A normal sperm has an oval head and a long tail, which work together to propel it forward. Sperm with large, small, tapered or crooked heads or kinky, curled or double tails are less likely to fertilize an egg.
- Motility. To reach the egg, sperm have to move on their own — wriggling and swimming the last few inches to reach and penetrate the egg. You're most likely to be fertile if more than 40 percent of your sperm are moving.
What's the best way to produce healthy sperm?
You can take simple steps to increase your chances of producing healthy sperm. For example:
- Take a multivitamin. A daily multivitamin can help provide vitamin E and vitamin C — nutrients that are important for optimal sperm production and function.
- Eat plenty of fruits and vegetables. These foods are rich in antioxidants, which may help improve sperm health.
- Manage stress. Stress may interfere with certain hormones needed to produce sperm. Stress can also decrease sexual function.
- Get plenty of physical activity. Physical activity is good for reproductive health as well as overall health. Don't overdo it, however. If you exercise to exhaustion, you may experience a temporary change in hormone levels and a drop in sperm quality.
- Watch your weight. Too much body fat may disrupt production of reproductive hormones, which can reduce your sperm count and increase your percentage of abnormal sperm. You're most likely to produce high-quality sperm if you maintain a healthy weight.
What's off-limits?
Sperm can be especially vulnerable to environmental factors, such as exposure to excessive heat or toxic chemicals. To protect your fertility:
- Avoid tobacco. If you use tobacco, ask your doctor to help you quit. Smoking can cause sperm to be misshapen and move slowly. In addition, smoking can damage your sperm's DNA, possibly affecting a baby's growth, development and risk of cancer. Chewing tobacco also may cause low sperm counts.
- Limit alcohol. Heavy drinking can reduce the quality and quantity of sperm. If you choose to drink alcohol, limit yourself to no more than one or two drinks a day.
- Steer clear of illicit drugs. Marijuana can decrease sperm motility and increase the number of abnormal sperm. Cocaine and opiates can contribute to erectile dysfunction.
- Skip the tub. Spending more than 30 minutes in water that's 104 F (40 C) or above may lower your sperm count. Avoid hot tubs and steamy baths. Saunas may have a similar effect.
- Limit your time on the bike. Sitting on a bicycle seat for more than 30 minutes at a time — especially if you also wear tight bicycle shorts — may raise your scrotal temperature and affect sperm production. If you bike, choose a bike seat that's not too hard or narrow, and make sure it's adjusted to keep weight on your "sit bones." While you're biking, stop for frequent rests.
- Stay cool. Increased scrotal temperature can hurt sperm production. Hot work environments, tight underwear, prolonged sitting and use of laptop computers directly on your lap can all increase scrotal temperature. A fever also can affect sperm production and quality.
- Avoid lubricants during sex. Personal lubricants, lotions and even saliva can interfere with sperm motility. Instead, use vegetable, safflower or peanut oil.
- Avoid certain medications. Anabolic steroids, antibiotics and certain medications used to control chronic conditions, such as high blood pressure or inflammatory bowel disease, can reduce your fertility. Anti-androgens used to treat prostate enlargement and cancer interfere with sperm production. In addition, chemotherapy drugs and radiation treatment for cancer can cause permanent infertility. If you're considering cancer treatment, ask your doctor about saving and freezing your sperm (semen cryopreservation) beforehand.
- Watch out for toxins. Workplace and household substances — such as industrial heavy metals, pesticides and chemicals in solvents — may affect sperm quantity and quality. Use protective clothing, proper ventilation and face masks to reduce the risk of absorbing toxins.
Does aging affect sperm health?
Women aren't the only ones who have biological clocks. Growing older — beyond age 50 — may affect male fertility by reducing sperm motility and the amount of normal sperm. Some research also suggests that women who become pregnant by older men are at higher risk of miscarriage and that children of older men have a slightly higher risk of certain birth defects, autism and cognitive impairment.
When is it time to seek help?
Adopting healthy lifestyle practices to promote your fertility — and avoiding things that can damage it — may improve your chances of conceiving. If you and your partner haven't gotten pregnant after a year of unprotected sex, however, ask your doctor about a semen analysis. A fertility specialist also may be able to identify the cause of the problem and provide treatments that help place you and your partner on the road to parenthood.
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