Understanding Polycystic Ovary Syndrome (PCOS): A Metabolic and Hormonal Disorder

Asst. Prof. Dr. Nur Wa Bushra Jahan
Patient, Proposal, Society

25

Aug 25

Abstract
Polycystic Ovary Syndrome (PCOS) is a complex endocrine and metabolic disorder affecting reproductive-aged women globally. Its pathophysiology involves hormonal imbalances, insulin resistance, and chronic inflammation, leading to long-term health consequences including infertility, type 2 diabetes, cardiovascular disease, and endometrial cancer. This article explores the definition, pathogenesis, cellular impact, prevalence, link with diabetes, classification as a metabolic syndrome, and approaches to management and prevention of PCOS.

Introduction

Polycystic Ovary Syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age. Characterized by a constellation of symptoms including hyperandrogenism, oligo-anovulation, and polycystic ovaries, PCOS affects multiple body systems and contributes significantly to female infertility, insulin resistance, and increased cardiometabolic risk.

What Is PCOS?

PCOS is defined by the presence of at least two of the following three criteria (Rotterdam criteria, 2003):

  • Oligo-ovulation or anovulation,
  • Clinical or biochemical signs of hyperandrogenism,
  • Polycystic appearing ovaries visible on ultrasound and also excluding other endocrinopathies having a similar clinical presentation.

This heterogeneous disorder presents differently across individuals, with symptoms ranging from irregular menstrual cycles to hirsutism, acne, alopecia, obesity, and infertility. Importantly, not all women with PCOS have cysts on their ovaries, and not all with ovarian cysts have PCOS1.

Causes and Pathophysiology

The exact etiology of PCOS remains unclear, but it is believed to result from a combination of genetic, hormonal, environmental, and lifestyle factors. A strong familial link suggests a genetic predisposition, while epigenetic changes influenced by fetal and postnatal environmental exposures may contribute to its development2.

Key Pathophysiological Drivers:

  1. Insulin Resistance (IR):
    Over 50% to 70% of women with PCOS have insulin resistance, independent of obesity. IR results in compensatory hyperinsulinemia, which enhances ovarian androgen production by stimulating theca cells and suppressing hepatic production of sex hormone-binding globulin (SHBG), thereby increasing free testosterone levels3.
  2. Hyperandrogenism:
    Elevated androgens disrupt the normal hormonal axis, impair follicular development, and contribute to anovulation. Androgens also drive clinical symptoms like hirsutism and acne.
  3. Hypothalamic-Pituitary-Ovarian (HPO) Axis Dysfunction:
    Increased frequency and amplitude of GnRH (gonadotropin-releasing hormone) pulses lead to a higher LH:FSH ratio, contributing to the excess production of androgens and disrupted folliculogenesis4.

Hormonal Effects on Cellular Function

Hormonal imbalances in PCOS impact several cellular pathways:

  • Theca cells in the ovaries become hyperresponsive to LH, leading to excess androgen production.
  • Adipocytes show impaired insulin signaling, contributing to inflammation and oxidative stress.
  • Endometrial cells experience prolonged unopposed estrogen stimulation due to lack of progesterone from anovulation, increasing endometrial hyperplasia and cancer risk.
  • Pancreatic β-cells undergo hyperactivity to counter insulin resistance, which may lead to eventual β-cell exhaustion and diabetes.

Global Prevalence

PCOS affects approximately 5% to 18% of women of reproductive age, depending on the diagnostic criteria and population studied5. Prevalence is rising in parallel with increasing rates of obesity and sedentary lifestyles. In South Asian populations, including India and Bangladesh, studies suggest a higher prevalence of PCOS—up to 22.5% in some urban cohorts6.

PCOS and Its Relation to Diabetes

PCOS is a precursor to metabolic syndrome and type 2 diabetes. Several mechanisms underlie this connection:

  • Insulin resistance is central to both PCOS and diabetes.
  • Chronic hyperinsulinemia eventually impairs β-cell function.
  • Elevated androgens exacerbate insulin resistance.
  • Inflammation and adiposity (especially visceral fat) further promote glucose intolerance.

Women with PCOS have a 4- to 7-fold increased risk of developing type 2 diabetes compared to women without PCOS7. Even lean women with PCOS have impaired glucose tolerance and should be screened periodically.

PCOS as a Metabolic Syndrome

Metabolic syndrome is a cluster of conditions abdominal obesity, hypertension, dyslipidemia, and insulin resistance that increase cardiovascular risk. PCOS meets many of these criteria:

  • Insulin resistance is intrinsic to PCOS.
  • Dyslipidemia (elevated LDL, low HDL, high triglycerides) is common.
  • Obesity especially central obesity is present in 40%–80% of PCOS cases.
  • Hypertension is frequently observed in PCOS women, even at a young age.

Several guidelines now view PCOS as a metabolic disorder rather than a purely reproductive condition8.

How to Overcome PCOS

There is no universal cure for PCOS, but the condition can be managed effectively with a combination of lifestyle interventions, medications, and supportive therapies. The treatment is individualized based on symptoms and goals (e.g., fertility vs. metabolic health vs. cosmetic concerns).

1. Lifestyle Modification (First-line Therapy)

  • Diet: Low glycemic index diets, Mediterranean-style diets, and high-fiber meals help control insulin and reduce weight9.
  • Exercise: Regular aerobic and resistance training improves insulin sensitivity and aids in weight loss.
  • Weight Management: Losing even 5–10% of body weight can restore ovulation and improve metabolic parameters.

2. Medications

  • Metformin: Improves insulin sensitivity, reduces hepatic glucose output, and can help regulate cycles10 and restores normal ovulation function.
  • Oral Contraceptives: Regulate menstrual cycles, reduce androgen levels, and protect against endometrial hyperplasia.
  • Anti-Androgens: Spironolactone and finasteride reduce hirsutism and acne.
  • Myoinositol and d-chairoinositol (DCI): Reduces fasting insulin plasma levels in obese PCOS and increases insulin sensitivity in non-obese PCOS.

3. Fertility Support

  • Ovulation Induction with letrozole or gonadotropins is effective.
  • IVF (In vitro fertilization) is an option for those who do not respond to simpler measures.

4. Mental Health Support

PCOS is linked with higher rates of anxiety, depression, and eating disorders. Cognitive behavioral therapy and support groups are recommended alongside medical treatment11.

Conclusion

Polycystic Ovary Syndrome is more than a reproductive disorder—it is a systemic condition with profound metabolic, endocrine, and psychological implications. Early diagnosis and individualized, multi-disciplinary management can reduce long-term complications like infertility, diabetes, cardiovascular disease, and mental health issues.

Recognizing PCOS as a metabolic syndrome allows clinicians and patients alike to focus not only on short-term symptoms but also on long-term health outcomes. Lifestyle modification remains the cornerstone of treatment, while pharmacological interventions and fertility support are tailored based on individual needs.

With global prevalence rising, particularly in South Asia and among young women, PCOS deserves attention as a public health priority. Holistic strategies incorporating nutrition, exercise, education, and mental health care can empower women to manage PCOS and improve quality of life.

Authors of this article

Asst. Prof. Dr. Nur Wa Bushra Jahan, MBBS (DMC), FCPS (Gyne & Obs) DMU (AIMS), Trained in Laparoscopy and Infertility (Malaysia), Post-Graduation Diploma in Reproductive Medicine (Germany)
Consultant: Department of Reproductive Endocrinology and Infertility (BSMMU)

References

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