Reproductive factors implicated in atrial fibrillation risk in women

Reproductive factors such as irregular menstrual cycles, nulliparity, and multiparity contribute to an increased risk of new-onset atrial fibrillation (AF) in women, as reported in a study.

The population-based cohort study drew data from the UK Biobank and included 235,191 women (mean age 55.7 years) without AF and history of hysterectomy and/or bilateral oophorectomy at baseline.

All participants completed questionnaires to provide data on sex-specific risk factors, including age at menarche, history of irregular menstrual cycle, menopause status, age at menopause, years after menopause, age at first live birth, years after last birth, history of spontaneous miscarriages, history of stillbirths, number of live births, and total reproductive years.

Over a median follow-up period of 11.6 years, a total of 4,629 (2.0 percent) women experienced new-onset AF. In multivariable Cox regression models, the risk of AF was higher among women with a history of irregular menstrual cycle (hazard ratio [HR], 1.34, 95 percent confidence interval [CI], 1.01–1.79).

AF incidence was also associated with both early menarche (age 7–11 years; HR, 1.10, 95 percent CI, 1.00–1.21) and late menarche (age 13–18 years; HR, 1.08, 95 percent CI, 1.00–1.17), as well as early menopause (age 35–44 years; HR, 1.24, 95 percent CI, 1.10–1.39) and delayed menopause (age ≥60 years; HR, 1.34, 95 percent CI, 1.10–1.78).

Other risk factors for AF were having 0 live births (HR, 1.13, 95 percent CI, 1.04–1.24) or ≥7 live births (HR, 1.67, 95 percent CI, 1.03–2.70) relative to having 1–2 live births.

The findings underscore the importance of considering the reproductive history of women in devising screening strategies for AF prevention.