Understanding PCOS: Symptoms, Diagnosis and Treatment

Polycystic ovary syndrome affects roughly one in ten women, and it is one of the most commonly misunderstood diagnoses in gynaecology — including by women who already have it.

What PCOS actually is

Despite the name, PCOS is not primarily a disease of cysts. The follicles seen on ultrasound are not cysts at all: they are immature eggs that stalled part-way through development because ovulation did not complete.

At its core, PCOS is a hormonal and metabolic condition. Higher levels of androgens interfere with normal ovulation, and in many women insulin resistance drives the process further.

How it is diagnosed

Diagnosis requires two of the following three, once other causes have been excluded:

1. Irregular or absent ovulation — typically cycles longer than 35 days, or fewer than eight periods a year
2. Clinical or laboratory evidence of excess androgens — acne, unwanted hair growth, scalp thinning, or a raised testosterone level
3. Polycystic ovarian appearance on ultrasound

Note carefully: a scan alone does not diagnose PCOS. Many women with entirely normal cycles have polycystic-looking ovaries, and being told you have PCOS on the basis of a single scan is one of the most common errors I correct in clinic.

The symptoms, and what causes each one

• Irregular periods: ovulation is not completing, so the hormonal signal to shed the lining never arrives on schedule.
• Difficulty conceiving: not because the eggs are poor, but because they are released unpredictably or not at all.
• Acne and unwanted hair: the direct effect of raised androgens on skin and follicles.
• Weight that resists dieting: insulin resistance makes fat storage easier and fat loss slower — it is a physiological headwind, not a failure of willpower.
• Hair thinning at the crown: androgenic effect on the scalp, and often the most distressing symptom of all.
• Mood and anxiety symptoms: genuinely more common in PCOS, and worth treating in their own right.

Why it matters beyond fertility

PCOS carries a higher long-term risk of type 2 diabetes, gestational diabetes, high cholesterol and high blood pressure. If periods are very infrequent, the uterine lining can also thicken over years without regular shedding, which raises the risk of endometrial changes.

This is why treatment is worthwhile even for women who are not trying to conceive — and why an annual review matters.

Treatment: matched to what you want now

If you want regular cycles and clearer skin

Combined hormonal contraception regulates bleeding, protects the lining and reduces androgenic symptoms. Anti-androgen medication may be added where acne or hair growth is prominent.

If you are trying to conceive

Ovulation induction is the first-line approach, usually with letrozole, which has better evidence than clomiphene in PCOS. Cycles are monitored by ultrasound so we can see whether a follicle is genuinely developing. Metformin is added where insulin resistance is significant.

If the metabolic side is the priority

A five to ten percent reduction in body weight can restore ovulation in a substantial proportion of women. Resistance training improves insulin sensitivity more efficiently than cardiovascular exercise alone, and a lower-glycaemic eating pattern is more effective than simple calorie restriction.

What to expect at your appointment

A proper PCOS assessment involves a cycle history, examination, pelvic ultrasound and blood tests including testosterone, LH, FSH, AMH, thyroid, prolactin, fasting glucose or HbA1c, and a lipid profile. You should leave with a diagnosis or a clear reason why it is not PCOS — not a prescription and a shrug.

This article is general information and does not replace a consultation. PCOS management is highly individual.