In a study, the more time men spent talking on the devices, the lower their sperm counts
NEW ORLEANS—Using a cell phone for several hours a day may be associated with a decrease in semen quality, data suggest.
How cell phone use might exert this effect is unclear, but researchers say the decrease in semen parameters appears to be dependent on the duration of daily exposure to cell phones.
“In our study we found that the higher the use of the cell phone the [greater] the decrease in four of the important sperm parameters: count, motility, viability and normal morphology,” said lead investigator Ashok Agarwal, PhD, director of the Reproductive Research Center at the Cleveland Clinic in Ohio.
“We are conducting a follow-up study to look at the mechanism of action. One of the possibilities is that Leydig cells, which are present in the testes, are very susceptible to electromagnetic waves.” He presented findings here at the 62nd annual meeting of the American Society of Reproductive Medicine.
Dr. Agarwal and his colleagues conducted a study with 361 men undergoing infertility evaluations from September 2004 through October 2005. The men were divided into four groups according to their cell phone usage. Group I: no use (40 men); Group 2: less than two hours a day (107 men); Group 3: two to four hours a day (100 men); and Group 4: at least four hours a day (114 men).
The investigators found that sperm count, motility, viability, and normal morphology decreased with increasing use of cell phones. Patients who used a cell phone for more than four hours a day had the greatest decrease in sperm count, total motility, percentage normal morphology, and viability.
“We think there may be several things going on here,” Dr. Agarwal said. “It may not just be the electromagnetic waves that are affecting spermatogenesis. One possibility may be that there is an increase in tissue temperature because of the absorption of the electromagnetic waves by the tissues around the testes. This is a preliminary study and there are several limitations so it is too soon to say infertile men should not use cell phones.” The study did not account for electromagnetic waves from sources such as radio towers, laptop computers, and other electronic devices.
This is not the first study to show potential harmful effects on the human body from cell phone usage. Previous studies have shown that electromagnetic waves alter and disturb sleep (J Sleep Res. 2002;4:289-295), and increase resting BP (Lancet. 1998;351:1857-1858). Other investigators have also linked electromagnetic waves to DNA strand breaks, headaches, fatigue, difficulty in concentration, and reduction in melatonin. A decrease in melatonin, which is an antioxidant, can predispose sperms to oxidative stress.
Dr. Agarwal’s group is conducting a prospective study in the Cleveland Clinic to further investigate this issue in more than 200 infertile men. In addition, many multicenter studies are also being planned.
Stanton Honig, MD, associate clinical professor of surgery/urology at the University of Connecticut in Farmington, said the data are interesting but require cautious interpretation. “This preliminary study does suggest that differences do occur within each group.
However, there are no data from fertile men for comparison,” said Dr. Honig, who is on the editorial advisory board of Renal & Urology News. Animal studies or comparisons with a fertile population would evaluate whether a relationship between cell phone use and male infertility has any clinical or scientific basis.