Earlier age at menopause, work, and tobacco smoke exposure.

OBJECTIVE: Earlier age at menopause onset has been associated with increased all-cause, cardiovascular, and cancer mortality risks. The risk of earlier age at menopause associated with primary and secondary tobacco smoke exposure was assessed.
DESIGN: This was a cross-sectional study using a nationally representative sample of US women. A total of 7,596 women (representing an estimated 79 million US women) from the National Health and Nutrition Examination Survey III were asked time since last menstrual period, occupation, and tobacco use (including home and workplace second-hand smoke [SHS] exposure). Blood cotinine and follicle-stimulating hormone levels were assessed. Logistic regressions for the odds of earlier age at menopause, stratified on race/ethnicity in women 25 to 50 years of age and adjusted for survey design, were controlled for age, body mass index, education, tobacco smoke exposure, and occupation.
RESULTS: Among 5,029 US women older than 25 years with complete data, earlier age at menopause was found among all smokers and among service and manufacturing industry sector workers. Among women age 25 to 50 years, there was an increased risk of earlier age at menopause with both primary smoking and SHS exposure, particularly among black women.
CONCLUSIONS: Primary tobacco use and SHS exposure were associated with increased odds of earlier age at menopause in a representative sample of US women. Earlier age at menopause was found for some women worker groups with greater potential occupational SHS exposure. Thus, control of SHS exposure in the workplace may decrease the risk of mortality and morbidity associated with earlier age at menopause in US women workers.