In my experience as a GP, PCOS is one of the most underdiagnosed and most misunderstood conditions I see. Women come to me after years of being told their irregular periods are "just stress" or "just how you are." They have been prescribed the contraceptive pill to regulate their cycles without being told why their cycles were irregular in the first place. Some have spent years trying to conceive without anyone investigating whether PCOS might be the reason.
The diagnosis is often straightforward once someone thinks to look for it. Let us start there.
What PCOS actually is
Polycystic Ovary Syndrome is a hormonal condition affecting the ovaries. Despite the name, "polycystic" does not mean the ovaries are covered in cysts in the traditional sense — it means they contain many small follicles (immature eggs) that have not developed and released normally.
PCOS involves three main features (the Rotterdam Criteria — you need two of the three for diagnosis):
- Irregular or absent ovulation — irregular periods, or no periods
- Signs of excess androgens — elevated testosterone on blood tests, or physical signs (excess facial/body hair, acne, hair thinning)
- Polycystic ovaries on ultrasound — many small follicles visible
It is one of the most common hormonal conditions in women of reproductive age, affecting approximately 1 in 10.
Symptoms — what women actually experience
The symptoms of PCOS vary considerably between women, which is part of why it goes undiagnosed:
Menstrual irregularities: Cycles longer than 35 days, fewer than 8 periods per year, or no periods. Some women have regular periods but still have PCOS.
Excess hair growth (hirsutism): Male-pattern hair growth — upper lip, chin, chest, stomach, inner thighs. Caused by elevated androgens.
Acne: Particularly along the jawline and chin — hormonal acne pattern.
Hair loss: Thinning at the crown (male-pattern), also androgen-related.
Weight gain: PCOS is associated with insulin resistance, which promotes weight gain and makes weight loss harder. Not all women with PCOS are overweight — this is a common misconception.
Difficulty conceiving: PCOS is the most common cause of anovulatory infertility (inability to conceive due to lack of ovulation).
Mood effects: Anxiety and depression are significantly more common in women with PCOS. The relationship is bidirectional — hormonal imbalance affects mood, and stress worsens PCOS symptoms.
Case study: Zainab's 6-year journey to diagnosis
Zainab, 31, came to see me after having been told by two previous GPs that her irregular periods were "nothing to worry about" and that she was "probably just stressed." She had been having periods every 50–80 days since she was 17. She had developed significant facial hair in her early 20s which she managed by threading. She had acne along her jawline.
She had never been offered a blood test or an ultrasound.
I ordered a hormone panel (LH, FSH, testosterone, SHBG, prolactin, thyroid function) and an ultrasound. Her testosterone was elevated. Her LH:FSH ratio was raised. Her ultrasound showed polycystic morphology bilaterally.
Diagnosis: PCOS. She was 31. She had had symptoms since 17.
"I feel relieved but also angry," she told me. "Not at you specifically. Just... why did nobody look sooner?"
I did not have a satisfying answer. I am sorry it took so long. The answer, partly, is that irregular periods in young women are often normalised when they should be investigated.
Diagnosis — what to ask your doctor for
If you suspect PCOS, ask your GP for:
- Hormone blood tests: LH, FSH, total testosterone, SHBG (sex hormone binding globulin), prolactin, AMH (anti-Müllerian hormone), thyroid function
- Metabolic tests: Fasting glucose and insulin (to assess insulin resistance), HbA1c, lipid panel
- Pelvic ultrasound
The blood tests should ideally be done in the early follicular phase of your cycle (days 2–5 if you have regular cycles). If you have no periods, they can be done at any time.
Management — what actually helps
PCOS has no cure, but symptoms are highly manageable.
Lifestyle (the most important intervention): For women with insulin resistance (most women with PCOS), even modest weight loss — 5–10% of body weight — can significantly restore ovulation and reduce symptoms. A low-glycaemic diet (reducing refined carbohydrates, increasing fibre and protein) helps regulate insulin levels. Regular exercise — both aerobic and resistance training — improves insulin sensitivity.
The contraceptive pill: The combined oral contraceptive pill regulates periods, reduces androgen levels (improving acne and hirsutism), and protects the uterine lining. It does not treat the underlying condition but manages symptoms effectively.
Metformin: An insulin-sensitising medication originally developed for diabetes, now used off-label in PCOS. Evidence supports its use in improving ovulation, reducing androgen levels, and improving metabolic markers. Particularly useful for women with insulin resistance.
Clomifene (clomiphene): First-line treatment for ovulation induction in women trying to conceive with PCOS. Works in approximately 70–80% of cases.
Spironolactone: For hirsutism and acne — reduces androgen effect. Not used if trying to conceive.
Inositol (myo-inositol): A supplement with emerging evidence for PCOS — improves insulin sensitivity and ovulation. Not licensed as a medication but widely used. Discuss with your doctor.
Long-term health risks
PCOS is associated with increased long-term risks that are worth monitoring:
- Type 2 diabetes: Up to 50% of women with PCOS will develop type 2 diabetes or prediabetes by their 40s — regular HbA1c monitoring is essential
- Cardiovascular disease: Related to the metabolic effects of insulin resistance
- Endometrial cancer: Long periods without menstruation allow the uterine lining to thicken. Regular periods (natural or induced by medication) protect against this.
- Mental health: Ongoing higher rates of anxiety and depression
Sources: Rotterdam ESHRE/ASRM Consensus 2003; NICE Clinical Guideline — Fertility Problems (NG156, 2023); Teede HJ et al, Human Reproduction 2018 (International PCOS Guidelines); Balen AH et al, BJOG 2016.