A laptop computer, or simply laptop or notebook, is a small mobile computer that usually runs on a single main battery or from an external AC/DC adapter which can charge the battery while also supplying power to the computer itself. This very useful office and entertainment tool is now being examined so that the public may be forewarned about the potential hazards of long-term use.
Researchers found that when a man balances the said equipment it on his lap, it increases the temperature of the scrotum which is known to have a negative effect on sperm production, and may cause scrotal hyperthermia. Since the function of the scrotum is to keep the testes at a temperature slightly lower than that of the rest of the human body, increase in scrotal temperature can damage sperm production and development. Scrotal hyperthermia has been identified as a risk factor for male infertility.
According to Dr. Yefim Sheynkin, lead researcher from the State University of New York at Stony Brook, laptops can reach internal operating temperatures of over 70°C --- a temperature that is harmful to live sperm.
“They are frequently positioned close to the scrotum, and as well as being capable of producing direct local heat, they require the user to sit with his thighs close together to balance the machine, which traps the scrotum between the thighs,” he said.
There are 29 healthy males aged between 21 and 35 who volunteered to be a part of the experiment. Temperature changes to the scrotum caused by laptop use and the different seating positions over one hour time periods were recorded and evaluated. The following results were observed: In order to balance a laptop, a man has to sit with his thighs together. With this posture alone, temperature in the scrotum rose by 2.1°C. When the men used a laptop in this position, the average temperatures increased by 2.6°C. on the left side of the scrotum and 2.8°C. on its right side.
Researchers also say that the body needs to maintain a proper testicular temperature for normal sperm production and development, or what is termed as spermatogenesis, in medical terms. Their studies have not determined the exact frequency and time of heat exposure that is capable of producing reversible or irreversible changes in spermatogenesis. But previous studies made suggest that 1°C above the baseline is the possible minimal thermal gradient. Based on their findings, the repetitive use of a laptop near the proximity of the male pelvic area might cause permanent damage and infertility. Teenage boys and young men are advised to limit their use of laptop computers on their laps until further studies provide more information on this type of thermal exposure.
At the British Fertility Society conference, Dr Allan Pacey, senior lecturer in Andrology at the University of Sheffield, said that it is already a common knowledge that increasing the temperature of the testicles can affect sperm production. He added that, “... worrying about having a laptop on your knees for only an hour can increase the temperature of the scrotum so significantly.” He warned that men who use laptops regularly should be very careful. Further work is needed to see if regular laptop use is a risk factor in male fertility and man's sexual health, in general.
