Dysmenorrhea and cold exposure.

As part of a health study undertaken at the request of the employees of eight Quebec poultry slaughterhouses, 213 women workers and 105 housewives responded to a self-administered questionnaire on menstruation. The prevalence of dysmenorrhea among the workers was determined for the last menstrual period and compared with that in the reference group, consisting of full-time housewives married to male slaughterhouse workers. The women slaughterhouse workers had a significantly higher prevalence of dysmenorrhea (73.2%) than the housewives (52.5%) (alpha less than 0.001). This difference was analyzed with respect to factors reported to be related to dysmenorrhea--age, parity, oral contraceptive use and menstrual regularity. Forty-four slaughterhouse workers took sick leave during their last menstrual cycle. The relationship between the prevalence of dysmenorrhea, sick leave and cold exposure at the workplace was examined. Among the workers the prevalence of dysmenorrhea and sick leave increased with increasing cold exposure (alpha less than 0.05 and less than 0.02, respectively). An analysis of the relationship of dysmenorrhea to cold exposure with respect to age, parity, oral contraceptive use and menstrual regularity revealed that factors usually associated with a lower frequency of dysmenorrhea do not apply to women working in a cold environment. These findings indicate that cold exposure influences the menstrual process.