What is PCOS (polycystic ovary syndrome)?
Polycystic ovary syndrome (PCOS) is a common hormone condition affecting about 1 in 10 people with ovaries. It is diagnosed when at least two of three features are present: irregular or absent ovulation, signs of high androgens such as excess hair or acne, and many small follicles on the ovaries on ultrasound. An international expert group has proposed renaming it polyendocrine metabolic ovarian syndrome (PMOS).
Common signs
- Irregular, infrequent or absent periods (oligomenorrhea)
- Excess facial or body hair, acne, or thinning scalp hair
- Difficulty getting pregnant, because ovulation is irregular
- Weight gain or difficulty losing weight, and insulin resistance
- Higher rates of anxiety and low mood
What causes it
The exact cause is unknown. It runs in families, and insulin resistance and higher levels of androgens play a central role. High insulin pushes the ovaries to make more testosterone, which disrupts follicle growth, so ovulation happens less often. The "cysts" are actually many small follicles that paused, not true ovarian cysts.
Managing PCOS
There's no single cure, but symptoms can be treated: lifestyle changes, the pill or other hormones to regulate periods, metformin for insulin resistance, treatments for hair and acne, and ovulation medicines such as letrozole for fertility. PCOS is linked to type 2 diabetes and heart risk, so regular checks matter. Read the full guide to PCOS and tracking periods with PCOS.
PCOS and mood
Depression and anxiety are more common with PCOS. Unpredictable cycles, body image worries and fertility stress all add up. Mood deserves as much attention as periods in your care.
Frequently asked questions
Can you have PCOS with regular periods?
Yes. If you have high androgens and polycystic ovaries on ultrasound, you can meet the criteria even with regular cycles.
Can you get pregnant with PCOS?
Yes. Many people with PCOS conceive naturally or with help such as ovulation induction.
Sources
- NHS: Polycystic ovary syndrome
- ACOG: Polycystic Ovary Syndrome (PCOS)
- MedlinePlus: Polycystic Ovary Syndrome
This page is for information only and isn’t medical advice. If something worries you, please talk to a doctor.
Keep reading
PCOS (now also called PMOS) and your cyclePCOS, now also called PMOS, explained: the common signs, how doctors diagnose it, what it does to your cycle and mood, and what helps day to day.PCOS period tracker: how to track a cycle that won't follow the rulesHow to use a PCOS period tracker when cycles are long or unpredictable: what to log, why ovulation tests can mislead, and the patterns your doctor needs.What is oligomenorrhea?Oligomenorrhea means infrequent periods, with cycles longer than 35 days or fewer than 9 periods a year. Common causes like PCOS, and when to see a doctor.Androgens: definition and meaningAndrogens are hormones like testosterone and DHEA that everyone makes. What they do in women, how they link to PCOS, and signs your levels may be high.Ovulation calculator for irregular periods: find your real windowOvulation calculator for irregular periods: enter your last period dates to see the full range of days you could ovulate, plus how to narrow it down. Free.