STANFORD, Calif., May 16 (UPI) -- Men with two or more abnormalities in their semen -- semen volume, sperm counts, motility and shape -- were more than twice as likely to die during an eight-year study period compared with men with normal semen. Lead author Dr. Michael Eisenberg, assistant professor of urology and Stanford University School of Medicine's director of male reproductive medicine and surgery, said about 1 in 7 couples in developed countries are affected at some point with infertility.
Eisenberg and senior authors Dolores Lamb and Dr. Larry Lipshultz, both of Baylor College of Medicine, analyzed medical records of about 12,000 men ages 20 to 50 who had been evaluated for possible infertility from 1994 to 2011 at Stanford Hospital & Clinics or between 1989 and 2009 at the Baylor College of Medicine in Houston.
Using data in the National Death Index and the Social Security Death index, the researchers compared mortality information with sperm quality.
Of the 11,935 men who were tracked, 69 died -- a seemingly small number, but the median age of the study subjects was age 36.6, and participants wanted to have children and tended to have a higher-than-average socio-economic status, better diets, education and access to healthcare.
Those trying to have a child are probably reasonably healthy and planning for the future, Eisenberg said.
The study, published in Human Reproduction, found the greater the number of semen abnormalities, the higher the mortality rate. The difference remained after factoring in for baseline health differences age and known diseases.