PCOS is common, commonly missed, and badly named, so let's clear it up.
It affects roughly one woman in ten, and a large share of them do not know. Women routinely spend years and several appointments getting a name for it, which is a long time to be told that irregular periods are just how you are.
Despite the name, PCOS isn't fundamentally about ovarian cysts. The "cysts" are small follicles, and you do not need them to have the condition. It's really a condition involving higher androgen levels (hormones like testosterone), irregular or absent ovulation, and often insulin resistance (the body responding less efficiently to insulin).
Doctors diagnose it when at least two of three features are present, after ruling out other causes:
That last line changed in 2023, and it matters. The international guideline now accepts anti-Müllerian hormone as an alternative to the ultrasound in adults, which means a diagnosis no longer has to wait on a scan.
More useful still: where both irregular cycles and signs of high androgens are present, neither a scan nor AMH is needed at all. If you have been sent away because a scan was normal, or told you cannot be assessed without one, that is out of date.
Adolescents are deliberately treated differently. In the years after periods start, both high androgens and irregular ovulation are required, and ultrasound and AMH are not recommended at all, because normal teenage ovaries look like PCOS ovaries far too often to be useful.
This explains most of the confusion, including your friend's PCOS looking nothing like yours.
Because diagnosis needs two of three features, there are four different combinations, and they behave differently. A woman with high androgens and absent ovulation tends to have the strongest metabolic picture. A woman with irregular cycles and the ovary appearance alone, with normal androgens, has a milder one. Same label, different condition, different priorities.
It is a spectrum, which is why generic PCOS advice so often misses, and why the right question is not "do I have PCOS" but "which parts of it do I have".
The stereotype is a woman carrying extra weight. It is wrong often enough to be harmful.
Insulin resistance is common in PCOS independently of weight, which means slim women get it too, and get dismissed for it too, because they do not look the part. If you are lean with irregular cycles and acne or unwanted hair, you have not ruled anything out. You have simply lost the visual cue that makes doctors think of it.
The reverse deserves saying as well. The 2023 guideline explicitly asks clinicians to be aware of weight stigma, because women with PCOS are told to lose weight so reflexively, and so often instead of being assessed, that many stop going.
Because insulin resistance is often involved, PCOS is linked to a higher long-term risk of type 2 diabetes and heart problems, which is exactly why managing it pays off for the whole body, not just the cycle. The 2023 guideline is blunt about this: every woman with PCOS should have her cardiovascular risk factors assessed.
Three other things belong on this list and rarely make it:
Your womb lining. If you ovulate rarely, the lining is exposed to oestrogen without progesterone to balance and shed it, and over years that raises endometrial cancer risk. This is the reason infrequent periods get treated rather than shrugged at, and the reason "I just don't bleed much" is not the good news it sounds like. Guidance is that very long gaps between periods should be managed rather than left.
Sleep apnoea, which is more common in PCOS and which makes the insulin picture worse, and which almost nobody screens for.
Pregnancy. PCOS carries a higher risk of gestational diabetes and blood-pressure problems, so it is worth flagging to whoever looks after you, early.
Anxiety and depression are markedly more common in women with PCOS. Not slightly. Studies put the odds of depression at around two and a half times higher, and anxiety similar.
This is not a footnote about how upsetting the symptoms are, though they are. It is a core feature of the condition, and the 2023 guideline singled it out for stronger recognition precisely because it gets treated as an afterthought. If you have PCOS and you are struggling with your mood, you are not failing to cope with a skin problem. You are experiencing the condition. See cortisol, stress and your hormones.
On that last point, the options are worth knowing by name, because "go on the pill" is often where the conversation both starts and ends. Combined hormonal contraception manages cycles, acne and unwanted hair and protects the womb lining. Metformin helps the metabolic side. Anti-androgen medicines address hair and skin. Which of these suits you depends entirely on which parts of PCOS you have and what you want from the next few years.
Inositol deserves an honest line, because it is everywhere. The evidence for cycle regularity and insulin sensitivity is genuinely promising and genuinely inconsistent, and it has not been adopted as standard care. It is a reasonable thing to discuss. It is not a replacement for the conversation.
PCOS is the most common cause of ovulatory infertility, and most women with PCOS who want a baby will have one.
Those two sentences belong together, because the first is usually delivered without the second. Ovulation is irregular, not impossible, and it responds to treatment well. The 2023 guideline names letrozole as the preferred first-line medicine for ovulation induction, ahead of clomiphene, which is a change many women have not been told about. Where those fail, there are second and third lines, including IVF.
Two practical notes. Irregular ovulation makes conception harder to time, not impossible, which is exactly why it also makes contraception necessary if you do not want to conceive. And modest weight loss, where there is weight to lose, can restore ovulation on its own. See trying to conceive over 35.
Go in with specifics rather than a feeling:
And know the line that matters: if your cycles are irregular and you have signs of high androgens, you meet the criteria without a scan.
PCOS is a spectrum, it's manageable, and small consistent changes often improve symptoms meaningfully. It is also lifelong: periods eventually stop, but the metabolic features do not, so the foundations stay relevant long after fertility stops being the question.
If the signs above sound familiar, it's worth asking your doctor. Getting a name for it is often the first relief, and for most women it is also the first time anything they have been told about their body has fitted together.
Can you have PCOS without cysts?
Yes. The name is misleading. Diagnosis rests on irregular ovulation, signs of high androgens, and the ovary appearance or a raised AMH, and where the first two are both present neither a scan nor AMH is needed.
Does PCOS go away at menopause?
Periods stop, but PCOS-related metabolic features persist, so the healthy-lifestyle foundations remain important throughout life. The diagnosis is best thought of as lifelong.
Can you be slim and have PCOS?
Yes. Insulin resistance in PCOS occurs independently of weight, and lean women are diagnosed later precisely because they do not fit the stereotype.
Can you get pregnant with PCOS?
Most women with PCOS who want to conceive do. Ovulation is irregular rather than absent, and it responds well to treatment; letrozole is now the preferred first-line medicine.
What blood tests diagnose PCOS?
There is no single test. Testosterone and SHBG assess androgens, AMH can stand in for the ultrasound in adults, and other tests exist mainly to exclude conditions that mimic PCOS, such as thyroid disease and raised prolactin.
Does PCOS cause depression?
Anxiety and depression are substantially more common in women with PCOS, with roughly two and a half times the odds. The 2023 guideline treats this as a core feature rather than a side note.
Sources: Teede HJ et al., Recommendations from the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, Human Reproduction 2023;38(9):1655-79 (published jointly in J Clin Endocrinol Metab and Eur J Endocrinol) · Monash University / international guideline summary, 2023 · Educational only, not medical advice.
Keep reading: Oestrogen dominance, explained · Adult hormonal acne · Hair thinning and hormones · Should you get your hormones tested? · Free PCOS symptom checker · Take the free Hormone Quiz