Sitting too long with a laptop computer on your lap may do more than cause toasted skin syndrome. New research suggests that men who hold a computer on their lap may create unsafe levels of testicular heat, which can potentially damage sperm.
The problem isn’t so much the heat generated from the computer itself, but the position required to keep the computer on the lap — knees together. In a recent study of 29 young men using laptop computers on their laps, with their legs held together for long periods, the temperature of their scrotums rose quickly — increasing up to 2.5 degrees C after an hour — enough to damage sperm, according to previous research. (More on Time.com: 5 Pregnancy Taboos Explained (or Debunked))
“Within 10 or 15 minutes their scrotal temperature is already above what we consider safe, but they don’t feel it,” the study’s author, Yelim Sheynkin, a urologist at the State University of New York at Stony Brook, told Reuters. (More on Time.com: Are You Fertile? Don’t Rely on a Drug-Store Fertility Test to Tell You)
Using a laptop pad resulted in less heat exposure to the skin, but the researchers said it didn’t do much to reduce scrotal temperature. Spreading the legs wider appeared to help initially, but ended up merely delayed overheating of the scrotum. Reuters reports:
“I wouldn’t say that if someone starts to use laptops they will become infertile,” Sheynkin told Reuters Health, though he warned that frequent use might contribute to reproductive problems because “the scrotum doesn’t have time to cool down.”
It’s been a bad couple of weeks for male fertility news: in the first human study on sperm quality and exposure to the plastics chemical bisphenol A (BPA), which was released at the end of October, researchers found that high BPA exposure was linked to low sperm count. The AP reported:
The study involved 130 Chinese factory employees who worked directly with materials containing BPA and 88 workers who didn’t handle it and whose exposure was similar to that of typical American men.
Low sperm counts were found in workers who had detectable levels of bisphenol-A in their urine. Poor sperm quality was two to four times more prevalent among these men than among workers whose urine showed no sign of BPA. The lowest sperm counts were in men with the highest levels of BPA.
BPA in urine was linked with lower-quality semen even in men who didn’t work with the chemical, although their average BPA levels were much lower than in the other group. [Study author Dr. De-Kun] Li said the average level in this group was similar to that detected in U.S. men.
BPA is ubiquitous — found in plastics, linings of metal food cans and dental sealants, among other sources — and the U.S. government is still evaluating its safety. (Canada has already declared the chemical toxic.) Meanwhile, a recent study by researchers at the University of Texas School of Public Health in Dallas found low but detectable levels of BPA in 63 out of 105 samples of food products from grocery stores; canned food had the highest levels. (More on Time.com: Want to Freeze Your Biological Clock? One Doc Says, Go For It)
Both male fertility studies were published in the journal Fertility and Sterility.
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