Abstract
PURPOSE: To characterize global temporal trends in the incidence of polycystic ovary syndrome (PCOS) from 1990 to 2021 by applying an age-period-cohort (APC) analytical framework across 204 countries and territories, and to assess how these incidence patterns vary according to socio-demographic context. METHODS: This study analyzed PCOS incidence trends from 1990 to 2021 across 204 countries using an APC analysis. Data were sourced from the Global Burden of Disease Study 2021, focusing on crude and age-standardized incidence rates, disaggregated by region and socio-demographic index (SDI). RESULTS: The global incidence of PCOS increased from 1.48 million cases in 1990 to 2.3 million in 2021. The age-standardized incidence rate in 2021 was 63.26 per 100,000 population (95% CI: 45.41 to 87.28). High SDI regions recorded the highest incidence rates, with a rate of 90.13 per 100,000 (95% CI: 66.94 to 122.36). In contrast, low SDI regions had the lowest incidence rates at 36.8 per 100,000 (95% CI: 25.83 to 52.19). The APC model revealed a global net drift of 0.18 (95% CI: -0.02 to 0.37), with significant age and period effects, particularly among younger age groups. CONCLUSION: This APC analysis reveals marked increases in global PCOS incidence driven by adolescent age groups, mid-2000s period effects, and recent birth cohorts. Findings underscore the need for age- and cohort-targeted interventions and harmonized diagnostics to address the growing PCOS burden.