Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by hyperandrogenism, ovulatory dysfunction and often insulin resistance. It reflects dysregulation across hypothalamic–pituitary–ovarian (HPO) and metabolic axes rather than isolated ovarian pathology.

HPO Axis and Ovarian Physiology

In PCOS, GnRH pulses from the hypothalamus and LH/FSH secretion from the pituitary are altered, often with an increased LH:FSH ratio. Elevated LH stimulates theca cells in the ovary to produce excess androgens (testosterone, androstenedione).
Granulosa cells may exhibit impaired aromatase activity, limiting conversion of androgens to estrogens. Follicular development stalls, leading to multiple small antral follicles and chronic anovulation.

Insulin Resistance and Metabolic Factors

Many individuals with PCOS display peripheral insulin resistance, with compensatory hyperinsulinemia. Insulin acts synergistically with LH on theca cells, further boosting androgen production. Adipose tissue dysfunction, inflammatory cytokines and altered adipokine profiles (leptin, adiponectin) contribute to metabolic risk.

Hyperandrogenism and Clinical Manifestations

Elevated androgens drive hirsutism, acne and androgenic alopecia. In the skin and hair follicles, androgen receptors mediate increased sebum production and terminal hair growth. In ovarian tissue, hyperandrogenism interferes with normal folliculogenesis and ovulation, contributing to subfertility.

Long-Term Risks

PCOS is associated with increased risk of type 2 diabetes, dyslipidemia, hypertension and possibly endometrial hyperplasia due to unopposed estrogen exposure. Mood and anxiety disorders are also more prevalent, highlighting the need for integrated care.

Treatment Implications

• Lifestyle interventions (nutrition, physical activity) to improve insulin sensitivity.
• Pharmacologic options: combined oral contraceptives, insulin sensitizers (e.g. metformin), antiandrogens when appropriate.
• Individualized reproductive planning and mental health support.

PCOS thus represents a network‑level disturbance of endocrine and metabolic regulation. Multimodal treatment can meaningfully modify both symptoms and long‑term health risks.