Polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome is the most common hormonal condition in women of reproductive age, and one of the most poorly named. The "cysts" on an ultrasound are not cysts. They are ordinary follicles — small fluid-filled sacs, each holding an immature egg — that have begun to develop and then stalled, because the signal that selects one of them to mature each month is not arriving cleanly. An ovary with twenty of them is not a damaged ovary. It is an ovary with a queue.

The diagnosis rests on the Rotterdam criteria: two of three features, once the conditions that imitate PCOS have been excluded. The three are irregular or absent ovulation; hyperandrogenism, either clinical (hirsutism, persistent acne, scalp hair thinning) or biochemical on a blood test; and polycystic ovarian morphology on ultrasound. Two of three. This is why polycystic-looking ovaries on a scan, by themselves, are not PCOS — that appearance is common in young women with entirely regular cycles, and it is particularly unreliable in the years soon after periods begin, when many healthy ovaries look that way.

Underneath the criteria sits a self-sustaining loop. Insulin resistance means the body produces more insulin to do the same work. High circulating insulin does two things at once: it prompts the theca cells of the ovary to make more androgen, and it reduces the liver's production of sex hormone binding globulin, the protein that keeps testosterone bound and quiet. Less binding protein means more free testosterone in circulation even when the total value on the report looks unremarkable. Raised androgens interfere with follicle selection, so ovulation becomes irregular, and the altered pituitary signalling that follows — LH running high relative to FSH — drives yet more ovarian androgen. Each step feeds the next.

Two consequences of that loop are often left out of the consultation. First, when ovulation does not happen, no progesterone is produced in the second half of the cycle, and the endometrium continues to thicken under oestrogen without the shedding signal that opposes it. Over years, that is why prolonged absence of periods is taken seriously rather than treated as a convenience. Second, PCOS is a lifelong metabolic-endocrine condition, not a purely gynaecological one. Prediabetes and type 2 diabetes, fatty liver, raised triglycerides with low HDL, and obstructive sleep apnoea all cluster with it, and they arrive earlier than in women without PCOS.

Indian data suggests PCOS is common here, though estimates vary widely — published studies report figures from around one in twenty-five to more than one in five of reproductive-age women, depending on the criteria used, the region, and whether the population was urban or rural. The honest summary is that it is frequent and under-diagnosed, and that a single national figure does not exist.

ⓘThis information is educational and not a diagnosis.

Most women arrive with one of three stories: cycles that have become unpredictable, hair or skin changes that are hard to ignore, or difficulty conceiving. Many arrive having been told, repeatedly and without much else, to lose weight — usually after months of trying exactly that and watching the scale stay where it was.

Cycle irregularity here usually means bleeding at intervals longer than 35 days, fewer than eight or nine periods in a year, or long stretches with none. Some women bleed predictably and still do not ovulate every month, which is why a regular calendar is reassuring rather than conclusive.

Androgen features follow a recognisable distribution: coarse dark hair along the upper lip, chin and jawline, the mid-chest, the lower abdomen and inner thighs; acne that persists past the teenage years or returns in the twenties, often along the jaw; and thinning at the crown while the hairline stays intact. Darkened velvety skin at the back of the neck or in the armpits — acanthosis nigricans — is a visible marker of insulin resistance, and is frequently mistaken for poor hygiene, which it is not.

It is worth naming plainly that hirsutism and acne carry social weight in Indian families, particularly around marriage, and that the resulting distress is a legitimate reason to treat rather than a vanity to be dismissed. Depression and anxiety are meaningfully more common in PCOS, and disordered eating — often set in motion by years of blunt weight advice — is common and rarely asked about. These belong in the consultation alongside the blood tests.

Body composition matters more than the number on the scale. South Asian women develop insulin resistance at lower BMI than European populations, and the waist threshold used for Asian-Indian women is around 80 cm rather than the 88 cm applied elsewhere. A woman with a BMI of 23 and a waist of 84 cm has a metabolic picture that a BMI-only assessment misses. Equally, plenty of women with PCOS carry no excess weight at all.

The features listed below are different in kind. They are not typical PCOS and warrant assessment promptly.

Testing in PCOS answers three questions: does this pattern actually meet the criteria, is something else producing it, and what is the metabolic picture underneath.

For the first, the history usually does most of the work. Cycle length recorded honestly over several months, and an examination for hirsutism, acne and acanthosis nigricans, often establish two of the three Rotterdam features without a scan. Where a scan is used in an adult, the current threshold is a high antral follicle count per ovary or an increased ovarian volume; the older cut-off of twelve follicles was raised as ultrasound machines improved, which is one reason older reports and newer ones are not directly comparable. Anti-Müllerian hormone is now accepted in adults as an alternative to ultrasound in some guidance, though it is not a stand-alone diagnostic test and costs considerably more in most Indian labs.

For the second, a small and specific panel: thyroid function, prolactin, and 17-hydroxyprogesterone for non-classical congenital adrenal hyperplasia, which can present identically. Where androgen features have appeared quickly or are severe, testosterone and DHEAS are checked to look for an androgen-producing tumour or Cushing's syndrome. These are uncommon, and that is precisely why they are excluded once rather than worried about indefinitely.

For the third — the part most often skipped — glucose handling and lipids. An HbA1c is inexpensive and widely available at chain laboratories in most Indian cities; a 75g oral glucose tolerance test takes two hours but detects impaired glucose tolerance that an HbA1c smooths over. A fasting lipid profile, liver enzymes and vitamin D are reasonable at diagnosis, the last because deficiency is very common in Indian women. Blood pressure and waist circumference cost nothing and are frequently omitted.

Repeated hormone panels every few months rarely change management. Monitoring in PCOS is mostly metabolic, and mostly annual.

Treatment is directed at what is troubling you now and at the risk building quietly in the background. Both matter, and neither substitutes for the other.

Metabolic change, explained as mechanism rather than effort. Loss of around 5 to 10% of body weight restores ovulation in a meaningful proportion of women who carry excess weight, and improves androgen levels and insulin sensitivity. The reason is biological: reducing visceral fat lowers circulating insulin, which raises SHBG, which lowers free testosterone, which lets follicle selection resume. It is a lever on the loop, not a moral test. For women who are already lean, the same lever is pulled by composition and activity rather than by the scale.

Resistance training deserves specific mention. Muscle is the body's largest site of glucose disposal, and building it improves insulin sensitivity independently of weight change. Two or three sessions a week does more for the metabolic picture than adding cardio alone. Adequate sleep, and assessment for obstructive sleep apnoea where snoring and daytime sleepiness are present, sit alongside it.

Eating, within how Indian households actually eat. The common pattern — rice or roti with a small quantity of dal, sweetened tea between meals, biscuits, and little protein in a vegetarian diet — produces large glucose swings and leaves protein intake well below what is useful. Practical changes: protein at every meal from dal, rajma, chana, paneer, curd, soya or eggs; vegetables and fibre before the starch; smaller staple portions rather than absent ones; and reducing sweetened drinks and packaged snacks, which do more damage than the rice ever did.

Medicines, explained rather than prescribed here. The combined oral contraceptive pill regulates bleeding, protects the endometrium and reduces androgen effects on skin and hair; the debated points are its effect on insulin sensitivity, its suitability where there is migraine with aura or clotting risk, and how long to continue. Metformin improves insulin sensitivity, modestly helps cycle regularity, and has stronger evidence where glucose handling is already impaired than as a treatment for hirsutism. Anti-androgens such as spironolactone are used for hirsutism and acne, take several months to show effect, and require reliable contraception alongside. Letrozole is now first-line for ovulation induction, ahead of clomiphene. Myo-inositol shows early promise with limited trial evidence and variable product quality. Which of these suits you, if any, is a conversation with a doctor who knows your history.

Skin and hair need their own plan. Medicines slow new growth but do not remove hair already present; laser hair reduction addresses that, and cost and access vary enormously between metro clinics and smaller towns. Setting that expectation early prevents a great deal of disappointment.

Follow-up is annual and metabolic: weight or waist, blood pressure, glucose handling, lipids, and a direct question about mood. Small steps held consistently outperform intense phases that stop.

The most useful shift in PCOS is understanding that the irregular cycle is a visible symptom of an invisible metabolic pattern. Once that is clear, the plan stops being a list of foods to avoid and becomes a small number of changes aimed at the loop itself.

If you would like to work through what your own results mean — glucose, lipids, androgens, thyroid, vitamin D — and how they fit together, the Learning Session below covers reading blood reports in a small group, with time for questions.

If you have a folder of reports and a history that has not yet been put together into one picture, that is a conversation for a consultation rather than an article.