(HealthDay News) — Hard physical work, high blood pressure (BP) and taking multiple medications are among the factors that may lower sperm quality and make men less fertile, new research suggests.
The study was published in Fertility and Sterility.
“Nearly 15% of American couples do not get pregnant within their first year of trying,” and male infertility plays a major role, study senior author Germaine Buck Louis, PhD, director of the division of intramural population health research at the U.S. National Institute of Child Health and Human Development, said in an agency news release.
Dr. Buck Louis’s team looked at 456 men in Texas and Michigan (average age, 32 years) who were in committed relationships and had stopped using contraception. Most of the men (77%) were white and more than half had never impregnated a woman.
Semen analysis revealed that 13% of the men who had physically demanding jobs had low sperm counts, compared with 6% of those who didn’t exert themselves at work. No other work-related factors — such as heat, noise or prolonged sitting — appeared to affect semen quality.
Men who had been diagnosed with high BP also had a lower percentage of normally shaped sperm than those without high BP.
The researchers also found that men who took multiple medications were more likely to have low sperm counts. Fifteen percent of men who took two or more medications had sperm counts below 39 million, compared with 7% of those who took no medications.
“The good news is that these factors, if they are confirmed to have negative effects on male fertility, can potentially be modified by medical care or changing job-related behaviors,” Dr. Buck Louis said.