BERKELEY, CA (UroToday Inc.) - Normal spermatogenesis requires that the testes be cooler than body temperature. Elevations in scrotal temperature due to environmental and physiologic causes have been shown to have deleterious effects on normal sperm production. With advancing technology, and the increased use of portable computers, some are curious to know whether or not the use of computers placed on the lap may be a potential hazard to fertility. Sheynkin and colleagues from State University of New York at Stony Brook, Stony Brook , NY, performed a study to determine the effect of lap top computer use on scrotal temperature. Their findings were published in Human Reproduction.

They recruited twenty-nine male volunteers, 21 to 35 years old, with no previous history of testicular abnormalities or scrotal surgery. Each underwent two one hour sessions with scrotal temperature measurements taken every 3 minutes while in the same sitting position with and without an operating laptop computer on their lap. Measurements were made on different days in the same room in which the environmental temperature was kept constant. The subjects were dressed in the same causal attire on each test day. The scrotal temperatures were taken using cutaneous probes. One each was placed over the right and left testis.

They found no significant difference in baseline scrotal temperatures between the left and right sides. There was a significant increase in scrotal temperature over baseline with or without the laptop computer in place. Without the computer, the increase in temperature was 2.1oC bilaterally, and with the operating computer, the greater increases were 2.8oC on the right and 2.6oC on the left.

The authors conclude that the use of a working computer on the lap can cause a significant increase in scrotal temperature. This may adversely affect spermatogenesis. Therefore, this observation warrants further studies on the effects of heat generating devices placed on the lap and on further testing for potential impact on fertility.

Hum Reprod. 2004 Dec 9; [Epub ahead of print]