First study to investigate burden of infertility attributable to PCOS shows sharp rise in prevalence globally and regionally. More than 12 million women affected globally in 2019 compared with 6m in 1990. Weight control should be used to mitigate against this trend, say authors.
The first comprehensive analysis of infertility related to PCOS has shown that cases among women of reproductive age rose from 6 million in 1990 to 12.13m in 2019 across more than 200 countries and regions; and ‘increased sharply’ in most parts of the world (1).
The findings, say the authors, underline the need for more effective health interventions and ‘efficient preventative and managerial strategies’. Indeed, they urge that weight control should be used to reduce this trend especially in regions with high levels of social and economic development where the burden of PCOS-related infertility was found to be the greatest.
PCOS is the most common cause of anovulatory infertility, affecting up to 80% of women who do not ovulate during a menstrual cycle. However, no comprehensive and detailed epidemiological estimates have been reported of PCOS-related infertility in reproductive women (15 to 49 years) by age and socio-demographic index (SDI), at the global, regional, and national level.
Now, say the authors, their global, regional and national analysis based on up-to-date data across 204 countries and regions provides comprehensive evidence of the impact of PCOS on types of fertility including primary and secondary.
The authors used the Global Burden of Disease 2019 study (GBD 2019) which includes information from sources such as censuses, medical registries and demographic surveillance (2). The GBD 2019 categorised the 204 countries into five SDI quintiles (low, low-middle, middle, high-middle, and high) based on the SDI value of each nation in 2019; and grouped the countries into 21 regions and 5 super-regions including central Europe, East Asia and high-income North America.
The National Institutes of Health (NIH) definition was used by the GBD 2019 for the PCOS diagnostic criteria. Infertility was defined as the inability to establish a clinical pregnancy after 12 months or more of unprotected sexual intercourse. Primary infertility was defined as a woman who had not been pregnant before; and secondary as a woman who had conceived and successfully given birth yet was unable to do so subsequently. The authors do not refer to women who have conceived yet miscarried in the definitions of infertility which they use.
The number, rates per 100 000 persons, and average annual percentage changes (AAPCs) of prevalence and years lived with disability (YLD) were estimated globally, regionally, and nationally. The YLDs of infertility attributable to PCOS were calculated by multiplying primary infertility prevalence by its disability weight (0.008) and secondary infertility prevalence by its disability weight (0.005).
Results showed an upward trend overall in the global age-standardized prevalence rates (ASPRs) and YLD rates (global ASPR=223.50/100 000 persons in 1990 vs 308.25/100 000 in 2019; YLD rate=35.20 thousand in 1990 vs 69.70 thousand in 2019).
The burden of infertility attributable to PCOS – based on ASPR and YLD rates – was significantly greater overall in the high SDI region than in the other four SDI regions. The highest annual increases in ASPRs and age-standardized YLD rates were observed in the middle and low middle quintiles. This latter finding, say the authors, might be explained by the fact the disability-adjusted life years (DALY) related to obesity was on the increase from 1990 to 2019 in the middle and low-middle SDI regions but was declining in the high and high-middle SDI regions.
In 2019, high-income Asia Pacific had the greatest regional ASPR and age-standardized YLD rate of infertility followed by Western Europe and high-income North America; and nationally Italy had the greatest ASPR and age-standardised YLD.
The burden of infertility attributable to PCOS was lowest in the age groups 15 to 19 and 45 to 49 years and was stable in women aged 20–44 years, a finding which the authors say may result from the low prevalence of PCOS among women aged 45 to 49 years.
Despite the robust dataset underpinning this study, the authors acknowledge that some countries could only provide limited data which may result in an ‘underestimation of the burden of infertility attributable to PCOS’.In addition, they say the diagnostic criteria of PCOS are constantly changing, which may ‘induce bias of infertility attributable to PCOS’.
Other limitations include detection bias which would lead to a higher prevalence of PCOS and PCOS-related infertility in developed countries with comprehensive health systems and ‘greater willingness of the populace to seek medical attention’. As such, the authors say that the allocation of health resources in areas of low prevalence should not be ignored.
Recent PCOS guidelines highlighted the importance of preventing weight gain (3). This recommendation is echoed by the authors of this study who conclude that the rapid global increase in obesity may be at least partially linked to the burden of PCOS-related infertility. What also needs to be addressed, they add, is that IVF remains ‘inaccessible and underfunded’ even in high income countries where PCOS is more likely to be diagnosed.
1 Xingyu Liu, Jinjin Zhang, Shixuan Wang, Global, regional, and national burden of infertility attributable to PCOS, 1990–2019; Hum Reprod Jan 2024, vol 39 (1); 108–118; https://doi.org/10.1093/humrep/dead241
2 Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019; The Lancet Open October 2020; DOI:https://doi.org/10.1016/S0140-6736(20)30925-9
3 Helena J Teede HJ et al. Recommendations from the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. Hum Reprod Vol 38(9) September 2023; Pages 1655–1679; https://doi.org/10.1093/humrep/dead156