Polycystic Ovary Syndrome
A metabolic condition with a reproductive name
What it is
PCOS is diagnosed by the Rotterdam criteria — two of three: irregular or absent ovulation, clinical or biochemical excess androgens, and polycystic ovarian morphology on ultrasound. It is the most common endocrine disorder in women of reproductive age, causing irregular periods, acne, excess hair growth, and difficulty conceiving.
Why it matters
The name is actively misleading. The cysts are not the disease, and many women with PCOS do not have them — while insulin resistance, which the name never mentions, is central to the condition. This is why PCOS is as much a cardiometabolic disorder as a reproductive one: it substantially raises the risk of type 2 diabetes and fatty liver disease. Managing it as a fertility problem alone misses most of the risk.
What BioSignal knows about treating this
What works for Polycystic Ovary Syndrome
BioSignal’s clinical summary, most important first.
- Weight management where relevant — improves ovulation, androgens, and metabolic risk together
- Combined oral contraceptives for cycle regulation and hyperandrogenism
- Metformin for the metabolic component
- Letrozole — NOT metformin — as first-line for ovulation induction when fertility is the goal
- Regular screening for type 2 diabetes and cardiovascular risk
- Resistance training and physical activity (improve insulin sensitivity independent of weight)
Signal Records relevant to this condition
Interventions and contributing factors — some of these records describe a cause rather than a cure. The rating shown is BioSignal’s confidence in that Signal Record, not a claim about how well it treats this condition. Open any of them for the full evidence.
New to this? Read these first
How this usually unfolds
- Recognize risk factors
- Get diagnosed
- Track key biomarkers
- Lifestyle first
- Evidence-based treatment
- Long-term monitoring
Who is at risk
- Insulin resistance (central to the condition)
- Obesity (worsens it, though lean PCOS exists and is often missed)
- Family history
- Certain ethnic backgrounds (higher prevalence and metabolic risk)
How it's diagnosed
Rotterdam criteria: two of three — oligo/anovulation, clinical or biochemical hyperandrogenism, and polycystic ovarian morphology on ultrasound — after excluding other causes such as thyroid disease, raised prolactin, and congenital adrenal hyperplasia. Ultrasound is not required if the other two criteria are met, and it should not be used in adolescents.
Key biomarkers
Lifestyle
Explore this condition across BioSignal
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Frequently asked questions
Do I have to have ovarian cysts to have PCOS?
No — and the name has caused enormous confusion. Diagnosis requires two of three criteria, so you can have PCOS with entirely normal-looking ovaries. Conversely, polycystic-looking ovaries are common in women without the syndrome. The 'cysts' are not the disease.
Why is my doctor talking about diabetes when I came about my periods?
Because insulin resistance is central to PCOS, even though the name never mentions it. PCOS substantially raises the risk of type 2 diabetes and fatty liver, and that risk is present regardless of whether you want to get pregnant. Managing PCOS as a purely reproductive condition misses most of the long-term harm.
What's the best treatment if I'm trying to conceive?
Letrozole is first-line for ovulation induction — it outperforms metformin for this purpose, which surprises many people given how often metformin is prescribed in PCOS. Weight loss, where relevant, also improves ovulation. This is a conversation for a clinician who treats fertility.
Evidence summary
The Rotterdam criteria are the established diagnostic standard. Insulin resistance is central to PCOS pathophysiology, and its associations with type 2 diabetes and MASLD are well documented. Letrozole has randomised evidence of superiority over metformin for ovulation induction. Combined oral contraceptives are established for cycle regulation and hyperandrogenism, and lifestyle intervention improves both reproductive and metabolic outcomes.
References & sources
- International evidence-based guideline for the assessment and management of PCOS
- Rotterdam consensus criteria
- Randomised trials of letrozole versus clomiphene/metformin for ovulation induction
Educational information — not medical advice
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