PCOS (now called PMOS)
A common hormone condition behind irregular periods, extra hair, acne and fertility struggles. Now renamed PMOS, because it’s about hormones and metabolism, not cysts. Treatment targets what bothers you most.
How common: about 1 in 8 women, and possibly more common in Aboriginal and Torres Strait Islander women. Often missed or diagnosed late.
Signs: irregular or absent periods, extra facial or body hair, scalp hair thinning, acne, trouble losing weight, anxiety or low mood, and difficulty getting pregnant. It raises the long-term risk of type 2 diabetes and heart disease.
Diagnosis: adults need 2 of 3: signs of high male-type hormones (hair, acne or a blood test), irregular ovulation, and polycystic ovaries on ultrasound or a high AMH blood test, once thyroid and other causes are ruled out. Teenagers need both of the first two; ultrasound isn’t used.
The new name: PMOS stands for polyendocrine metabolic ovarian syndrome. Same condition, same diagnosis.
The PCOS ladder
There’s no single cure, so treatment is matched to your goal: regular periods, less hair, fertility, or lowering long-term diabetes and heart risk.
- Step 1 · Self-careActivity and healthy eating150–300 minutes of moderate activity a week (or 75–150 vigorous) plus strength work; about 250 minutes for modest weight loss.
- Works
- Recommended for everyone, mainly for metabolic health. No single diet beats the others
- Cost
- Free
- How long
- Ongoing
- Watch for
- Weight stigma helps no one; focus on habits, not just the scales.
There is no PCOS diet. There’s the one you can live with.
- Step 2 · PrescriptionCombined pillRegulates periods and lowers male-type hormones.
- Works
- First choice for irregular periods, excess hair and acne
- Cost
- Many under the $25 PBS co-payment
- How long
- Ongoing; hair takes 6+ months to respond
- Watch for
- Not suitable for everyone, such as some with clot risks.
Old, cheap and still first-line for good reason.
- Step 3 · PrescriptionMetforminA diabetes tablet used mainly for the metabolic side of PCOS, especially with a BMI of 25 or more.
- Works
- About as effective as an active lifestyle program for metabolic features
- Cost
- Under the $25 PBS co-payment, about $22–23
- How long
- Ongoing
- Watch for
- Stomach upset and diarrhoea; start low. More in our metformin guide.
A supporting act, not a magic fix.
- Step 4 · PrescriptionHair and skin treatmentsLaser for facial hair; anti-androgen tablets if other treatments fail or aren’t suitable.
- Works
- Laser works for facial hair in some people; anti-androgens have a limited role
- Cost
- Laser courses cost hundreds to thousands of dollars
- How long
- Months
- Watch for
- Anti-androgens need reliable contraception.
Hair is slow to leave. Be patient.
- Step 5 · PrescriptionWeight-loss medicinesMay be considered alongside lifestyle changes, using the same rules as for anyone else.
- Works
- Help with weight and metabolic health; see our weight sheet
- Cost
- Not on the PBS for weight loss; private scripts cost several hundred dollars a month
- How long
- Long term
- Watch for
- Not for pregnancy or when trying to conceive.
A useful tool for some, not a requirement.
- Step 6 · SpecialistFertility helpLetrozole tablets to trigger ovulation, then other options, then IVF if needed.
- Works
- Letrozole is the first-line tablet to help ovulation
- Cost
- GP or specialist fees; IVF costs vary widely
- How long
- Months
- Watch for
- Metformin isn’t routinely used in pregnancy.
PCOS makes pregnancy harder, not impossible.
Save your money
Popular, heavily marketed or often asked about, but the evidence is weak or says no.
- Inositol supplementsLimited benefit, not recommended for fertility, and no particular type or dose has good evidence. Metformin does more for hair and waist.
- Insulin blood testsNot recommended in routine care. They don’t change treatment.
- AMH or ultrasound alone for diagnosisAn AMH test can’t diagnose PCOS on its own, and neither test is used in teenagers.
- Home IPL hair-removal kitsNot shown to work for PCOS hair. Clinic laser has the evidence.
What you can do
- Track your cycles in an app or diary.
- Move most days and add strength work twice a week.
- Ask about regular checks of blood pressure, blood sugar and cholesterol.
- Tell your GP about low mood or anxiety; screening is recommended for everyone with PCOS.
See your GP if
- Periods are irregular, very infrequent or absent
- Extra hair, acne or hair thinning is bothering you
- You’re trying to get pregnant
- Low mood, anxiety or body image worries
See your GP promptly if new hair growth is rapid, or your voice deepens. Fast-changing male-type features point to other causes that need checking.
Common questions
Why has PCOS been renamed PMOS?
The new name, polyendocrine metabolic ovarian syndrome, reflects that it affects hormones and metabolism across the body, not just the ovaries. The condition and how it is diagnosed have not changed.
Can I get pregnant with PCOS?
Many people do. If you have trouble ovulating, letrozole tablets are the first-line treatment, with other options and IVF if needed.
Is there a special diet for PCOS?
No single diet has been shown to work better than others. Any healthy eating pattern you can keep up is fine, combined with regular activity.
Does inositol work for PCOS?
The benefit is limited. Guidelines say it can be considered if you prefer, but it is not recommended for fertility and no type or dose has good evidence.
Helpful resources
- Jean Hailes: PMOS (formerly PCOS)Women’s health organisation’s guide, with a symptom checklist. Free, Australia.
- 2023 International PCOS Guideline summaryThe evidence-based guideline behind most of this page. Free.
Evidence and more information
- Jean Hailes: PMOS (formerly PCOS)
- International evidence-based guideline for PCOS, 2023 summary (Monash University)
maladywise.com/pcos/