Male Infertility and Scrotal Temperature: A selection of the medical literature

1960’s I. Control of Human Spermatogenesis Intrascrotal Temperature The authors showed that alterations of intrascrotal temperature markedly affect spermatogenesis and sperm counts. In euspermic subjects, scrotal exposure for 30 minutes to a 150-watt electric light bulb resulted in reversal of the scrotal-rectal temperature ratio by a mean of 2.9 °C. Such treatment on 14 consecutive days caused depression of spermatogenesis followed by rebounds to temporarily high sperm counts. Application of an ice bag to the scrotum for a mean of about 30 minutes cooled the testicular environment by a mean of 6.9 C. Such cold treatment on 14 consecutive days, beginning not less than 12 days following cessation of exposure to heat, stimulated spermatogenesis without initial inhibition, nearly tripling the mean pretreatment count. (Robinson D, Rock J, Menkin MF. “Control of Human Spermatogenesis Intrascrotal Temperature.” JAMA. (1968); 204(4):290-297. doi:10.1001/jama.1968.03140170006002.)