Males who use laptops on their laps are likely to experience scrotal hyperthermia – elevated temperatures in their testicles – which can significantly affect the quality of their sperm, and consequently their fertility, US scientists report in the medical journal Fertility and Sterility. The authors add that even if they protect their laps with a lap pad, scrotal hyperthermia still occurs. The only way a male can be sure to protect his fertility when using a laptop is by placing it on a desk, using it with legs apart while using a lap pad for no longer than 28 minutes, or using the laptop on his lap with knees together for very short periods.

Yelim Sheynkin, M.D. (urologist) and team from the State University of New York at Stony Brook set out to evaluate how to prevent scrotal hyperthermia among male laptop users. Their study involved 29 health male volunteers.

The scientists measured the temperatures of the left and right side of the scrotum, as well as the laptop and lap pad during three separate 60-minute sessions – all the participants were using a laptop in the following ways:

  • Sitting with their knees together (approximated legs) and the laptop on their laps
  • Sitting with their knees together, laptop on lap, and with lap pad between their laptops and their laps
  • Sitting with their legs apart at a 70° angle, laptop on lap, and with lap pad between their laptops and their laps

Their goal was to measure any rise in scrotal temperatures.

The authors wrote that scrotal temperatures went up considerably, in spite of the position of their legs and whether or not they used a lap pad.

Scrotal temperature did go up less and the rise occurred later when the men had their legs apart at a 70° angle. However, even then, the rise in scrotal temperature was cause for concern.

Below are some of the highlighted results:

  • Knees together, laptop on lap (no lap pad)
    Scrotal temperature rise – left side from 0.96C to 2.31C, right side from 0.91C to 2.56C.
    The scrotum started rising in temperature within 11 minutes.
  • Knees together, laptop on lap, using lap pad
    Scrotal temperature rise – left side from 0.69C to 2.18C, right side from 0.72C to 2.06C.
    The scrotum started rising in temperature within 14 minutes.
  • Legs apart, laptop on lap, using lap pad
    Scrotal temperature rise – left side from 0.66C to 1.41C, right side from 0.62C to 1.47C.
    The scrotum started rising in temperature within 28 minutes.

The authors wrote in conclusion:

Sitting position with closely approximated legs is the major cause of scrotal hyperthermia. Scrotal shielding with a lap pad does not protect from scrotal temperature elevation. Prevention of scrotal hyperthermia in LC users presently is not feasible. However, scrotal hyperthermia may be reduced by a modified sitting position (legs apart) and significantly shorter use of LC.

“Protection from scrotal hyperthermia in laptop computer users”
Yefim Sheynkin, M.D., Robert Welliver, M.D., Andrew Winer, M.D., Farshid Hajimirzaee, M.D., Hongshik Ahn, Ph.D., Kyewon Lee, M.S.
Fertility and Sterility – 08 November 2010 (10.1016/j.fertnstert.2010.10.013)

Written by Christian Nordqvist