Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder in women of reproductive age, characterized by irregular menstruation and hyperandrogenism (1, 2). In 2021, the global standardized prevalence rate (ASPR) among women of reproductive age was as high as 3364.53 cases per 100,000 people (95% UI: 2395.08 - 4681.81) (3).Although the exact cause of PCOS is not fully understood, research indicates that it is closely related to genetic and environmental factors, with diet and lifestyle also playing a role (4). PCOS is a major cause of female infertility (5) and is associated with increased risks of insulin resistance, obesity, metabolic disorders, and cardiovascular diseases (6–8). Additionally, compared to non-PCOS individuals, patients with PCOS are more likely to experience anxiety, depression, low self-esteem, and decreased quality of life (9, 10). This not only affects the health of patients but also increases the economic burden on healthcare systems (11, 12). In 2020, estimated healthcare expenditures in the United States due to PCOS-related pregnancy complications and long-term diseases were approximately $43 billion (11). Therefore, considering the significant impact of PCOS on economic systems, individual health, and public health, conducting in-depth research on its epidemiological characteristics, identifying relevant influencing factors, and providing policy recommendations for disease screening and resource allocation are of utmost importance.

PCOS has become a significant issue affecting the health of women worldwide, presenting differentiated challenges in different regions and populations (13, 14). The diagnosis of PCOS is highly complex and challenging primarily because it requires ruling out other diseases that may cause similar symptoms, leading to underdiagnosis or delays in diagnosis (15–17).An estimated 70% of people with PCOS are undiagnosed meaning that the financial, personal and societal burden of this disorder are even higher than currently understood (18). This is especially true in low Socio-demographic Index (SDI) with limited medical resources and diagnostic technologies, where underdiagnosis not only affects patient health but also exacerbates the burden on the healthcare system (19, 20). Therefore, gaining a deeper understanding of the differences in disease burden across countries with different economic levels is crucial for improving the efficiency and equity of global healthcare systems. By allocating resources effectively, it is possible to improve the diagnosis and management of PCOS, thereby alleviating the current unfavorable trends.

Social changes and economic development have led to significant shifts in the global population structure (21). From 1990 to 2019, the global population increased by 43% (21, 22). This growth necessitates adjustments in national healthcare systems to address the impact of population growth on the health sector (21). However, the specific effects of global population growth on the burden of PCOS have not been systematically studied. This research gap may limit the ability of the World Health Organization and national governments to effectively address the increased health demands resulting from population growth when formulating and adjusting health policies. Moreover, an in-depth exploration of the epidemiological characteristics of PCOS globally and predicting its future trends holds significant potential value for disease prevention.

The objective of this study is to utilize the GBD statistical model to systematically describe the disease burden of PCOS in 2021 using the GBD statistical model, processing and analyzing data from global, regional, and national levels, and evaluating the temporal trends and epidemiological characteristics of PCOS. We also focus on age factors, as well as the association between PCOS and socio-economic status, conducting the first analysis of transnational inequalities in PCOS and frontier analysis, assessing the impacts of aging, population growth, and epidemiological changes on PCOS, and predicting trends up to 2035.

Our research indicates that the disease burden of PCOS are all on the rise. The age group with the highest incidence is predominantly 10–19 years old, while the number of cases and DALYs are mainly concentrated in the 15–49 age group. Countries with higher SDI levels bear a heavier burden of PCOS, especially in high-income Asia Pacific, Australasia, and Western Europe, with Italy and Japan facing particularly severe situations. Inequality persists, and no country is at the forefront of reducing the burden of the disease. Population growth and epidemiological changes are driving an increase in the burden of PCOS. The disease burden of PCOS is projected to continue to rise through 2035.

Since 1990, the global burden of PCOS has continued to increase, with the burden being most significant in high SDI regions. This is closely related to the lifestyle and dietary habits in high SDI regions, where high-calorie, high-fat, and high-sugar dietary patterns are closely associated with obesity and insulin resistance (32, 33) both of which are important risk factors for PCOS (34, 35). Additionally, in high SDI regions, abundant medical resources and advanced diagnostic technologies allow for PCOS patients to be identified and diagnosed earlier and more accurately (13, 36). The increasing awareness of women’s health is also an important factor driving the rise in PCOS diagnosis rates (37). Meanwhile, in moderate SDI regions, the burden of PCOS is growing at a rapid pace, particularly in rapidly urbanizing Southeast Asia. In addition to the influence of lifestyle and medical resources (38, 39), factors such as a high prevalence of metabolic syndrome (40) and changes in population demographics are major reasons for the increasing disease burden in this region (41, 42). Additionally, the widespread use of the Rotterdam criteria (43) has expanded the diagnostic criteria for PCOS, to more patients being diagnosed. This has, to some extent, increased the global burden of the disease (44, 45).

Based on our analysis of age distribution, we found that the peak incidence of PCOS is mainly concentrated in the 10–19 age group. This is because adolescence is a key stage for the development of the female reproductive system, where various organ systems are still developing, hormone levels fluctuate significantly, and the regulation of the hypothalamic-pituitary-ovarian axis is not fully matured, making hormonal imbalances more likely to occur (8, 46, 47). Although PCOS has a higher incidence during adolescence, its disease burden is more significant in the 15–49 age group. Women in this age group are more prone to obesity and metabolic abnormalities, factors that further exacerbate the burden of PCOS (48, 49). Additionally, women of childbearing age seek medical attention more frequently due to their reproductive health needs and issues such as irregular menstruation, infertility, acne, etc. This behavior increases the diagnosis rate of PCOS (50, 51). PCOS is a chronic condition that requires long-term management starting from adolescence. It is recommended to reduce the intake of high-sugar, high-fat, and high-salt foods while increasing the consumption of dietary fiber, whole grains, and vegetables (52, 53). Additionally, patients should increase their physical activity, control weight, actively regulate menstrual cycles, and improve their status through medication or lifestyle changes. It is also important to undergo regular screenings to reduce the burden of the disease and improve long-term health outcomes (54, 55).

The COVID-19 pandemic has changed the global landscape of disease burden, but Join-point results reveal that the pandemic has not affected the trend of the disease burden of PCOS (56–58). An important turning point was in 2016 when there was a slight increase in the global disease burden of PCOS. This temporal association might reflect, in part, improved diagnostic ascertainment following the 2016 publication of the article “Clinical Practice. Polycystic Ovary Syndrome” (59), although other factors such as technological advances and changing lifestyles likely contributed concurrently. While the Rotterdam criteria are widely used in clinical practice, there are still differences in diagnostic criteria and practices among different countries and regions (60), it is necessary to conduct in-depth research on the clinical characteristics and pathogenesis of PCOS using big data and multi-omics technologies to improve diagnostic criteria. Additionally, there is a need for enhanced international collaboration to integrate diagnostic experiences from different countries and regions. Furthermore, tailored diagnostic guidelines should be developed for adolescent women and special populations (such as obese patients) to reduce underdiagnosis and delays in diagnosis, thereby better-safeguarding women’s health.

The SDI is positively correlated with the ASR of PCOS but negatively correlated with the EAPC. Uneven economic development has had a significant impact on the allocation of healthcare resources and access to medical services. In high SDI regions, advanced healthcare and quality health services have enhanced diagnostic capabilities, while better medical interventions and health awareness have controlled the growth of the disease burden of PCOS (61–63). However, low SDI regions with limited resources and inadequate medical services have not achieved the same level of improvement (64, 65). It is crucial to promote the fair distribution of global healthcare resources, strengthen support for low SDI regions, and improve basic healthcare infrastructure and medical services. This emphasizes the importance of elevating the SDI as a core objective of health policies.

Cross-national inequality analysis shows that the relative inequality of PCOS has decreased, mainly attributed to the widespread dissemination of medical technology, strengthened international cooperation (66, 67), increased public health awareness (37), and greater emphasis on the management of non-communicable diseases (68, 69). These factors have collectively promoted the global standardization of PCOS diagnosis and management. However, absolute health inequality is on the rise, reflecting unequal distribution of healthcare resources, disparities in status, and variations in health awareness and education levels. In the future, it is imperative to further strengthen international cooperation and policy support, increase investment in healthcare resources for low SDI regions, raise public health awareness, and effectively narrow the gap in global health inequality. Furthermore, PCOS is classified as a “common gynecological disease” and suffers from systematic neglect. This often leads to insufficient investment in research funds, uneven distribution of specialized medical resources, and a reduction in the priority given to public health policies (70, 71). This results in a health inequality phenomenon where “the disease is prevalent but the resource allocation is unequal”. Therefore, incorporating gender as the core dimension in health equity analysis is necessary to truly reveal and improve the long-overlooked health disparities of this group.

Although the SDI levels are similar, there are still significant differences in the burden of PCOS among different countries and regions. These differences cannot be simply explained by the SDI levels. Essentially, they are the concrete manifestations of multi-dimensional differences such as cognition, healthcare, culture, and genetics in a specific disease. Even if the SDI levels are similar, it does not mean that the distribution of medical resources is uniform. The differences in the density of specialists and the accessibility of examinations within a region will directly be reflected in the diagnosis rate of PCOS (72, 73); even if the same diagnostic criteria are used, the medical traditions and clinical practice habits in different regions will cause deviations in the implementation of the standards, resulting in uneven diagnosis rates and disease awareness levels (74); cultural and gender perspectives indirectly affect the disease burden through influencing patients’ medical-seeking behaviors (75, 76); differences in dietary structure, sedentary habits, and life rhythms will directly affect the occurrence and development of PCOS (77); in addition, the genetic background of specific races may increase the susceptibility to the disease (78, 79). Overall, these differences are the result of the joint action of multiple factors such as medical resource allocation, social culture, lifestyle, genetic susceptibility, and diagnostic practices. In the future, in-depth research on the challenges faced by countries with poor performance in PCOS management and addressing knowledge gaps may help alleviate the disease burden of PCOS.

Population growth and epidemiological changes are driving the increase in the global burden of PCOS. The expansion of the population directly results in an increase in the absolute number of disease burden, highlighting the importance of addressing population growth issues and suggesting it may be a potential strategy to alleviate the disease burden of PCOS in specific regions. Additionally, epidemiological changes are reflected in improvements in diagnostic criteria and lifestyle modifications. Due to variations in the demographic and epidemiological patterns of PCOS globally, it is evident that specific preventive and management measures for PCOS need to be developed for different regions, countries, and even on a global scale.

Based on the BAPC model’s predictions, the disease burden of PCOS is projected to continue rising until 2035. PCOS is a key area for public health intervention and is preventable. Future progress in the treatment and management of PCOS, healthcare reforms, and global public health initiatives may significantly alter the predicted developmental trend of PCOS.

Our study has certain limitations, with the data sources and quality in the GBD database are inconsistent, especially in economically underdeveloped areas, where inadequacies in the healthcare system may lead to potential misdiagnosis and underdiagnosis issues. Despite using complex statistical models to adjust data errors, this may still affect the comparability of the data. The DALYs provided by GBD 2021 may not fully reflect the specific impact of polycystic ovary syndrome (PCOS) on patients’ daily life functions and mental health. As a forward-looking suggestion, future research should incorporate quality-adjusted life years (QALYs) to better capture the multi-dimensional quality of life deficits associated with PCOS, including psychological distress, body image issues, and the stress related to infertility, thereby providing a more patient-centered perspective on the disease burden.

Between 1990 and 2021, the global burden of PCOs has shown an overall increasing trend. However, due to the unequal distribution of healthcare resources and lifestyle differences, significant differences exist among different regions and countries. Countries with higher SDI levels, although having a heavier burden of PCOS, have effectively controlled the growth trend, while low SDI regions have not achieved the same level of improvement. Future research should prioritize the establishment of a standardized global framework for the diagnosis and data reporting of PCOS, deeply explore the challenges faced by countries with poor management performance to fill knowledge gaps, and deepen research on the disease mechanism to develop more precise prevention and treatment methods; at the policy level, gender equality should be incorporated into the core dimension of global health equity, increase resource investment in low SDI countries, conduct standardized diagnosis training, and formulate differentiated regional prevention strategies to narrow the resource gap; in clinical practice, the early screening of high-risk populations aged 10–19 should be optimized, and standardized diagnostic guidelines based on age stratification (especially during puberty) and specific phenotypes (such as obese type) should be established to reduce missed diagnoses and misdiagnoses, promote the integration of lifestyle intervention, psychological support, and long-term metabolism in a multidisciplinary comprehensive management model, and implement full-cycle management from adolescence to reproductive age; and through strengthening public health education to enhance disease awareness, effectively curb the growth of PCOS burden, and promote the balanced improvement of global female health levels.