Polycystic ovary syndrome, Body mass index, Obesity, Infertility, Insulin resistance.

PCOS is a hormonal disorder marked by an imbalance of sex hormones that primarily affects women of reproductive age.[1,2] Signs and symptoms that are associated with PCOS include irregular menstrual cycle, polycystic ovaries, hirsutism, obesity, acne, hyperandrogenism, insulin resistance, impaired glucose tolerance (Type 2 Diabetes), and infertility.[2,3] The majority of women with PCOS (38-88%) are either overweight or obese.[4,5] The level of obesity can be determined by using BMI. It is calculated by dividing the weight in kilograms by the square of the height in meters.[6] Adult BMI is classified into three categories: underweight (<18.5kg/m ²), normal weight (18.5kg/m ² to 24.9kg/m ²), overweight (25kg/m ² to 29.9kg/m ²), and obese (≥30kg/m ²).[7]

The etiology of PCOS has yet to be discovered, and there is no exact known cause at the moment. However, a genetic component as well as several additional risk factors, such as obesity and insulin resistance, have been identified.[8] In the current literature, there is a significant disparity in the BMI ranges associated with PCOS. Only a few researchers have investigated the relationship between BMI and PCOS. Due to variations with the diagnostic criteria for PCOS, these studies are frequently hampered by small sample sizes, selection bias, and are not comparable with the findings of other studies. The goal of this review is to evaluate the prevalence of PCOS based on ranges of BMI.

All the suitable databases such as Google Scholar, Springer, and PubMed were searched for relevant articles. Definition of BMI was obtained from WHO website.

Inclusion and exclusion criteria: Articles published before 2021 were considered in this review. Only articles demonstrating the prevalence of PCOS with BMI and obesity were chosen, while others were excluded.

The percentage of PCOS patients is higher at BMI >25kg/m ². i.e., it tends to increase beyond this value and decreases below this value (table 1).

Table 1: Showing average BMI and prevalence of PCOS based on Rotterdam criteria

PCOS is a major clinical issue of the present age that has been reported to affect 8%-13% of reproductive-aged women.[22] Obesity was first discovered to be a prevalent symptom of PCOS by Stein and Leventhal (1935) and later validated by many authors. Obesity has been estimated to affect up to 80% of PCOS women in the United States. According to a recent Spanish study, PCOS is five times more common in overweight or obese women of childbearing age (28.3%) as compared to the general population (5.5%).[23,24]

PCOS can appear at any time during a woman’s reproductive life; however, it is most common during adolescence.[25] The incidence rate of infertility in reproductive-age women begins to climb at a BMI of 24kg/m ² and continues to increase as BMI rises.[26] According to a study published in June 2009, women with PCOS have reduced levels of follicle-stimulating hormone (FSH) and increased levels of BMI as compared to normal women.[27]

Association between obesity and PCOS: The most frequent finding in women with PCOS is obesity, and it is estimated that about 40%–80 % of women suffering from this condition are either overweight or obese.[28] A recent systematic review of 35 studies found that overweight (BMI 25–30kg/m ²) and obesity (BMI ≥30kg/m ²) were about 2 and 2.8 times more common in women with PCOS, respectively.[29] Obesity is linked to changes in adipokine and inflammatory cytokine production, which may contribute to obesity-related insulin resistance and metabolic syndrome.[30] In culture, hyper-insulinemia has been demonstrated to promote ovarian androgen synthesis by acting as a co-gonadotropin.[31] Patients with PCOS who have a BMI of 23kg/m ² or more are more likely to develop metabolic disorders.[32] With increasing weight, the prevalence of dyslipidemia rises.[33] A similar association persists in the metabolic syndrome.[34] However, major multicenter research of women with PCOS reported no metabolic syndrome in those with PCOS and a BMI of 27kg/m ² test.[35]

It’s unclear whether obesity causes PCOS or PCOS causes obesity. However, androgen exposure in postmenopausal women is the main cause of increasing visceral adiposity in obese as well as normal-weight women.[36] Similarly, a recent study suggests that uncontrolled obesity before puberty combined with severe insulin resistance can lead to the development of PCOS later in life (Figure 1).[37]

Figure 1: Schematic representation of the development of PCOS in women

Obesity is also associated with elevated testosterone concentrations, suggesting increased androgen production.[38] Aromatase is a protein found in adipose tissue that promotes the synthesis of bioactive estrogens from androgens, which are then released into the bloodstream.[39] This can also cause elevated estrone levels, which have been observed in PCOS women.[40] According to a study published in 2011, elevated BMI levels are less specific than lipid accumulation product (LAP) in predicting Impaired glucose tolerance (IGT), confirming previous findings that LAP is better than BMI in predicting type 2 diabetes mellitus.[41-43]. This could be explained by the fact that an increase in BMI can be induced by an increase in lean mass or an enlargement of the protective subcutaneous adipose tissue (SAT) in the lower extremities.[44]

Figure 2: Showing the role of obesity in PCOS

Figure 3: Showing treatment measures for PCOS

Limitations: While performing this review, we had to face many problems. Many of the articles were inaccessible. Moreover, there were only a few articles published on the selected topic.

Recommendations: Treating obesity might be useful to control PCOS. This includes lifestyle modifications like exercise, weight loss, healthy diet, etc. Besides this, pharmacologic treatment, such as metformin and bariatric surgery, remains a last resort  and effective intervention. However, obesity is not a primary cause of PCOS, but rather a potential risk factor. So, further study is advised on the association of BMI with PCOS.

Our review suggests that there is a strong and positive relation between BMI and PCOS. The percentage of PCOS patients is higher at BMI >25kg/m ²test.

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Corresponding Author:
Mubashir Ali
Department of Radiological Sciences and Medical Imaging
University of Lahore, University Institute of Radiological Sciences and Medical Imaging, Lahore, Pakistan
Email: [email protected]

Co-Author:
Syed Zaigham Ali Sha
Department of Chief Radiology Technologist
Human resource development center (HRDC), Skardu, Pakistan

All authors contributed to the conceptualization, investigation, and data curation by acquiring and critically reviewing the selected articles. They were collectively involved in the writing – original draft preparation, and writing – review & editing to refine the manuscript. Additionally, all authors participated in the supervision of the work, ensuring accuracy and completeness. The final manuscript was approved by all named authors for submission to the journal.

Not applicable

Not reported

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https://doi.org/10.63096/medtigo30622438

Mubashir A, Syed ZAS. Ranges of Body Mass Index in Polycystic Ovary Syndrome: Maximum and Minimum. medtigo J Med. 2024;2(4):e30622438. doi:10.63096/medtigo30622438 Crossref