Whitcomb BW, et al. – This study entailed the exploration of the relation between cigarette smoking and risk of early natural menopause. The data disclosed that women who smoked ≤10 cigarettes/day but quit by age 25 exhibited a comparable risk to never–smokers. A dose–response association between smoking and early natural menopause risk, and reduced risk among quitters could yield insights into the mechanisms of cigarette smoking, on reproductive health.

Methods

• Data was extracted from the Nurses’ Health Study II of 116,429 nurses from 1989 through 2011.
• The Cox proportional hazards models calculated the hazard ratios (HR) adjusting for confounders.

Results

• The current smokers reported a HR of 1.90 (95% CI: 1.71, 2.11); former smokers displayed a HR of 1.10 (95% CI: 1.00, 1.21), compared to never-smokers.
• There exhibited increased risks among women reporting current smoking with a HR = 1.72 (95% CI: 1.36, 2.18) for 11-15 pack-years; HR = 1.72 (95% CI: 1.38, 2.14) for 16-20 pack-years; and HR = 2.42 (95% CI: 2.11, 2.77) for >20 pack-years.
• An elevated risk was noted in former smokers reporting 11-15 (HR = 1.29, 95% CI: 1.07-1.55), 16-20 (HR = 1.42, 95% CI: 1.13, 1.79) or >20 pack-years (HR = 1.54, 95% CI: 1.23, 1.93).
• A comparable risk to never-smokers (HR = 1.03, 95% CI: 0.91, 1.17) was noted among women who smoked ≤10 cigarettes/day but quit by age 25