Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-age women — characterised by combinations of menstrual irregularity (from anovulation), signs of excess male hormones (hyperandrogenism — hirsutism, acne, hair loss) and polycystic-appearing ovaries on ultrasound. It affects approximately 6-13% of women (up to 26% with broader criteria) — approximately 190 million women globally. Despite its name, "cysts" are actually multiple small follicles; PCOS is fundamentally a hormonal and metabolic condition.

PCOS is multifactorial — genetic predisposition (strong familial clustering; many susceptibility genes identified) plus environmental/lifestyle factors (obesity amplifies features). The key underlying mechanisms: insulin resistance (in approximately 70% of women with PCOS — causing compensatory hyperinsulinaemia that drives excess androgen production from the ovaries and adrenal glands); and hypothalamic-pituitary dysregulation (abnormal LH/FSH ratio driving excess ovarian androgen production and disrupting follicle development). Obesity exacerbates insulin resistance and worsens PCOS features — but PCOS also occurs in lean women.

What are the symptoms?

Menstrual irregularity: oligomenorrhoea (infrequent periods — <8/year) or amenorrhoea (absent periods) — from chronic anovulation. Hyperandrogenism: hirsutism (excess male-pattern facial and body hair — the most common sign); acne; androgenic alopecia (male-pattern hair thinning). Infertility: anovulatory infertility — PCOS is the most common cause of anovulatory infertility. Metabolic: weight gain; difficulty losing weight; darkening of skin in skin folds (acanthosis nigricans — a sign of insulin resistance). Psychological: depression, anxiety, body image concerns.

How is PCOS diagnosed?

The Rotterdam criteria (2003, most widely used) require at least 2 of 3 features after excluding other causes: (1) Oligo/anovulation (irregular or absent periods); (2) Clinical or biochemical hyperandrogenism (hirsutism/acne/elevated androgens); (3) Polycystic ovarian morphology on ultrasound. The 2023 WHO guideline updated the PCOM threshold to ≥20 follicles/ovary (from the older ≥12) using modern high-frequency ultrasound. Key exclusions: thyroid dysfunction, hyperprolactinaemia, congenital adrenal hyperplasia, and other androgen-excess disorders.

What are the treatments for PCOS?

Lifestyle modification: the first-line intervention — weight loss of 5-10% significantly improves menstrual regularity, hyperandrogenism, fertility and metabolic parameters. For menstrual regulation: combined oral contraceptive pill (OCP); cyclical progestogens (to prevent endometrial hyperplasia in anovulatory women). For hyperandrogenism: OCP; anti-androgens (spironolactone, finasteride). For metabolic features: metformin; inositol; weight management. For ovulation induction (fertility): letrozole (first-line — WHO 2023); metformin (adjunct); laparoscopic ovarian surgery (when clomiphene-resistant, 3rd line); gonadotropins; IVF.

Why was letrozole recommended over clomiphene?

The 2023 WHO PCOS guideline recommends letrozole (an aromatase inhibitor) as the first-line pharmacological treatment for ovulation induction — replacing clomiphene citrate which had been the standard for over 50 years. A landmark 2014 NEJM trial (Legro et al.) showed letrozole achieved significantly higher live birth rates (27.5% vs 19.1%) and ovulation rates compared to clomiphene in women with PCOS. Letrozole produces mono-follicular ovulation (lower multiple pregnancy risk), has a shorter half-life (less anti-oestrogenic endometrial effect) and is equally safe. Clomiphene resistance (failure to ovulate) occurs in approximately 20-25% of women.

What are the long-term health risks of PCOS?

Metabolic: 4-7x increased risk of type 2 diabetes; impaired glucose tolerance in approximately 30-40%; metabolic syndrome in approximately 50% of overweight women with PCOS; elevated cardiovascular risk (hypertension, dyslipidaemia — though absolute cardiovascular event risk appears lower than feared in most longitudinal studies). Reproductive: endometrial hyperplasia and endometrial carcinoma risk from unopposed oestrogen (anovulation); pregnancy complications (gestational diabetes, preeclampsia, preterm birth). Psychological: depression (approximately 50%) and anxiety (approximately 60%).

Does PCOS cause infertility?

PCOS is the most common cause of anovulatory infertility — accounting for approximately 75% of anovulatory infertility cases. Anovulation prevents egg release, making conception impossible in most cycles. However, most women with PCOS can achieve pregnancy with appropriate treatment: lifestyle modification; letrozole (first-line ovulation induction); metformin (adjunct); gonadotropin injections; laparoscopic ovarian surgery (drilling); or IVF. The key challenge is often achieving a healthy weight first — obesity substantially reduces treatment success rates.

How does GMJ News cover PCOS?

GMJ News covers WHO PCOS guideline 2023, letrozole vs clomiphene evidence, metabolic complications, psychological burden, insulin resistance management and the PCOS infertility treatment pathway. PCOS is the most common endocrine disorder in Georgian reproductive-age women — directly relevant to PHIG's women's health programme and the Georgian Medical Journal.

Home › Topics › Polycystic Ovary Syndrome (PCOS)

Polycystic Ovary Syndrome (PCOS)

Q: How is PCOS diagnosed?

The Rotterdam criteria (2003, most widely used) require at least 2 of 3 features after excluding other causes: (1) Oligo/anovulation (irregular or absent periods); (2) Clinical or biochemical hyperandrogenism (hirsutism/acne/elevated androgens); (3) Polycystic ovarian morphology on ultrasound. The 2023 WHO guideline updated the PCOM threshold to ≥20 follicles/ovary (from the older ≥12) using modern high-frequency ultrasound. Key exclusions: thyroid dysfunction, hyperprolactinaemia, congenital adrenal hyperplasia, and other androgen-excess disorders.

Q: What are the treatments for PCOS?

Lifestyle modification: the first-line intervention — weight loss of 5-10% significantly improves menstrual regularity, hyperandrogenism, fertility and metabolic parameters. For menstrual regulation: combined oral contraceptive pill (OCP); cyclical progestogens (to prevent endometrial hyperplasia in anovulatory women). For hyperandrogenism: OCP; anti-androgens (spironolactone, finasteride). For metabolic features: metformin; inositol; weight management. For ovulation induction (fertility): letrozole (first-line — WHO 2023); metformin (adjunct); laparoscopic ovarian surgery (when clomiphene-resistant, 3rd line); gonadotropins; IVF.

Q: Why was letrozole recommended over clomiphene?

The 2023 WHO PCOS guideline recommends letrozole (an aromatase inhibitor) as the first-line pharmacological treatment for ovulation induction — replacing clomiphene citrate which had been the standard for over 50 years. A landmark 2014 NEJM trial (Legro et al.) showed letrozole achieved significantly higher live birth rates (27.5% vs 19.1%) and ovulation rates compared to clomiphene in women with PCOS. Letrozole produces mono-follicular ovulation (lower multiple pregnancy risk), has a shorter half-life (less anti-oestrogenic endometrial effect) and is equally safe. Clomiphene resistance (failure to ovulate) occurs in approximately 20-25% of women.

Q: What are the long-term health risks of PCOS?

Metabolic: 4-7x increased risk of type 2 diabetes; impaired glucose tolerance in approximately 30-40%; metabolic syndrome in approximately 50% of overweight women with PCOS; elevated cardiovascular risk (hypertension, dyslipidaemia — though absolute cardiovascular event risk appears lower than feared in most longitudinal studies). Reproductive: endometrial hyperplasia and endometrial carcinoma risk from unopposed oestrogen (anovulation); pregnancy complications (gestational diabetes, preeclampsia, preterm birth). Psychological: depression (approximately 50%) and anxiety (approximately 60%).

Q: Does PCOS cause infertility?

PCOS is the most common cause of anovulatory infertility — accounting for approximately 75% of anovulatory infertility cases. Anovulation prevents egg release, making conception impossible in most cycles. However, most women with PCOS can achieve pregnancy with appropriate treatment: lifestyle modification; letrozole (first-line ovulation induction); metformin (adjunct); gonadotropin injections; laparoscopic ovarian surgery (drilling); or IVF. The key challenge is often achieving a healthy weight first — obesity substantially reduces treatment success rates.

Q: How does GMJ News cover PCOS?

GMJ News covers WHO PCOS guideline 2023, letrozole vs clomiphene evidence, metabolic complications, psychological burden, insulin resistance management and the PCOS infertility treatment pathway. PCOS is the most common endocrine disorder in Georgian reproductive-age women — directly relevant to PHIG's women's health programme and the Georgian Medical Journal.

GMJ News knowledge hub · last reviewed September 2026 · Georgian Medical Journal

Summary Statistics Glossary GMJ news FAQ Documents Organizations Research

Polycystic ovary syndrome (PCOS) — the most common endocrine disorder in women of reproductive age — affects an estimated 190 million women globally (6-13% of reproductive-age women, rising to 20-26% with broader diagnostic criteria), causing a constellation of reproductive, metabolic and psychological disturbances (WHO). PCOS is associated with a 4-7 fold increased risk of type 2 diabetes, elevated cardiovascular risk, endometrial cancer risk and — in women seeking fertility — anovulatory infertility (letrozole, not clomiphene, is now WHO's recommended first-line ovulation induction). The 2023 WHO International Evidence-based Guideline on PCOS represents the first comprehensive global clinical standard for this condition.

Key messages

190 million women — most common endocrine disorder

PCOS affects approximately 190 million women globally (6-13% of reproductive-age women), making it the most common endocrine disorder in women — and the leading cause of anovulatory infertility (WHO 2023 International Evidence-based Guideline).

2023 WHO guideline — letrozole first-line

The 2023 WHO International Evidence-based Guideline on PCOS established letrozole (not clomiphene) as the recommended first-line pharmacological treatment for ovulation induction in PCOS — a landmark update replacing decades of clomiphene-first practice.

Metabolic complications dominate lifetime risk

PCOS carries a 4-7 fold increased risk of type 2 diabetes, significantly elevated cardiovascular risk, metabolic syndrome in approximately 50%, and endometrial cancer risk from unopposed oestrogen in anovulatory women.

Rotterdam criteria — diagnosis

PCOS is diagnosed by two of three criteria: oligo/anovulation; clinical or biochemical hyperandrogenism; and polycystic ovarian morphology on ultrasound (≥20 follicles per ovary or ovarian volume >10mL). Other conditions must be excluded.

Psychological impact is profound

Depression and anxiety affect approximately 50% and 60% of women with PCOS respectively — substantially higher than the general population. Body image concerns, hirsutism, acne, infertility and weight difficulties all contribute to psychological burden.

Lifestyle modification is first-line

Weight loss of 5-10% in overweight women with PCOS significantly improves menstrual regularity, reduces hyperandrogenism, improves insulin sensitivity and increases fertility. Lifestyle intervention is recommended before or alongside pharmacological treatment.

Key statistics

~190M

women with PCOS globally

WHO 2023

6-13%

of reproductive-age women affected (up to 26% with broader criteria)

WHO 2023

4-7x

elevated type 2 diabetes risk

WHO/Endocrine Society

50%

of overweight PCOS women have metabolic syndrome

WHO

2023

year of landmark WHO PCOS evidence-based guideline

WHO

6-10yr

average diagnostic delay from first symptoms

PCOS Society/research

PCOS manifestations — approximate frequency in women with PCOS (%) — WHO/research

Source: WHO/published data. Most women have multiple manifestations; presentation is highly variable.

Glossary of key terms

Rotterdam criteria
ESHRE/ASRMThe most widely used PCOS diagnostic criteria — requiring 2 of 3: oligo/anovulation (irregular periods); clinical/biochemical hyperandrogenism (excess male hormones); polycystic ovarian morphology on ultrasound (≥20 follicles/ovary or ovarian volume >10mL). Other causes must be excluded.

Hyperandrogenism
WHO/EndocrineExcess androgens (testosterone, DHEAS, androstenedione) — causing hirsutism (male-pattern hair growth), acne, and androgenic alopecia. Both clinical (physical signs) and biochemical (elevated serum androgens) hyperandrogenism are recognised in PCOS diagnosis.

Letrozole
WHO/FIGOAn aromatase inhibitor — now the WHO-recommended first-line ovulation induction agent for infertile women with PCOS (2023 guideline). Superior to clomiphene in live birth rates (NEJM 2014 landmark trial). Induces follicle development without raising oestrogen excessively.

Metformin
WHO EMLA biguanide insulin sensitiser — recommended by WHO for metabolic features of PCOS (impaired glucose tolerance, type 2 diabetes prevention) and as an adjunct to lifestyle modification. Improves menstrual regularity; modest ovulation induction benefit; reduces miscarriage risk in PCOS.

Inositol
WHO/ResearchA naturally occurring compound — particularly myo-inositol and D-chiro-inositol — with evidence for improving insulin sensitivity, ovarian function, and hormonal parameters in PCOS. Included in the 2023 WHO PCOS guideline as a treatment option; safe with few side effects.

Endometrial hyperplasia risk
WHO/FIGOChronic anovulation in PCOS causes prolonged unopposed oestrogen exposure to the endometrium — increasing risk of endometrial hyperplasia and endometrial carcinoma. Regular endometrial shedding (via cyclical progestogens or combined OCP) is recommended to mitigate this risk.