Rotating shift work may delay the onset of natural menopause, according to a study published online March 25 in Menopause.
Durdana Khan, M.P.H., from York University in Toronto, and colleagues used data from the Canadian Longitudinal Study on Aging database to identify 3,688 premenopausal women followed prospectively for three years. Associations between shift work exposure and the variations in age at natural menopause were examined.
The researchers observed a significant association between women who were ever exposed to shift work and a delayed onset of menopause versus daytime workers (hazard ratio, 0.77). Rotating shift work in the current and longest job period was associated with delayed onset of menopause compared with daytime work (hazard ratios, 0.64 and 0.65, respectively).
“This study shows a potential influence of circadian regulation on age at natural menopause, with current rotating shift work linked to later age at menopause and current night shift work linked to earlier age at menopause,” Stephanie Faubion, M.D., medical director of the North American Menopause Society, said in a statement. “Whether these differences in age at menopause are directly related to the effect of circadian rhythm changes on underlying hypothalamic regulation or are because of other sociodemographic factors such as chronic stress, economic insecurity, and substance use or abuse requires further study.”