Infertility and the Risk of Cardiovascular Disease: Findings From the Study of Women’s Health Across the Nation (SWAN)

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death in women globally. In recent years, attention has turned to infertility and pregnancy-related events as potential markers for early mortality and future CVD. METHODS: The Study of Women’s Health Across the Nation (SWAN) is an ongoing longitudinal cohort study of women’s health. Women aged 42-52 years with a uterus and ≤ 1 intact ovary, a menstrual period, and no hormone medications within 3 months before enrollment were eligible. Infertility was self-reported and defined as the inability to achieve pregnancy after 12 months of trying to conceive, or use of fertility medications for > 1 month. Outcomes included development of metabolic syndrome over a 7-year follow-up, and any atherosclerotic CVD event (ie, stroke, angina, myocardial infarction) over a 10-year follow-up. Cox proportional hazards models were used to calculate hazard ratios (HRs) for metabolic syndrome and CVD events in participants with infertility, with adjustment for relevant covariates. Participants without infertility were used as the comparison group. RESULTS: We included 2370 participants in the analysis of metabolic syndrome risk, and 2809 participants were included in the analysis of CVD event risk. Participants with self-reported infertility did not have a higher risk of developing metabolic syndrome (HR, 0.91; 95% confidence interval, 0.71-1.15) or experiencing CVD events (HR, 0.79; 95% confidence interval, 0.52-1.21) after adjusting for relevant covariates. CONCLUSIONS: Infertility was not associated with development of metabolic syndrome or CVD events in women; further research is required to investigate the effects of specific causes of infertility and fertility treatments on CVD outcomes.