Polycystic ovary syndrome (PCOS) is a common hormonal and metabolic condition that affects how the ovaries function. It can affect menstrual periods, ovulation, fertility, hair growth, skin and metabolic health. Despite the name, not everyone with PCOS has ovarian cysts.
Common symptoms
- Irregular periods, infrequent periods or no periods
- Excess facial or body hair
- Acne or oily skin
- Thinning scalp hair
- Difficulty becoming pregnant because ovulation is irregular
- Weight gain or difficulty managing weight in some people
- Darkened or thickened skin, particularly around the neck or under the arms
Diagnosis
There is no single test for PCOS. Assessment may include menstrual and medical history, signs of excess androgen activity, blood tests and sometimes pelvic ultrasound. Other conditions that can cause irregular periods or excess hair growth should be excluded. Diagnosis in adolescents requires particular care because some features overlap with normal puberty.
Treatment
Treatment is individualized according to symptoms, metabolic health and pregnancy plans. Regular physical activity, nutritious eating, adequate sleep and weight management when appropriate can support metabolic health. Medicines may be used to regulate menstrual cycles, manage acne or excess hair growth, improve insulin sensitivity or support ovulation and fertility.
Long-term health
PCOS is associated with an increased risk of type 2 diabetes and other cardiometabolic risk factors. Infrequent menstrual periods can also increase the risk of excessive thickening of the uterine lining. Follow-up may include assessment of blood pressure, blood glucose, cholesterol and menstrual health.
When to seek medical advice
See a healthcare professional if periods are very irregular or absent, symptoms are troublesome, or you have difficulty becoming pregnant. Sudden severe pelvic pain, fainting, very heavy bleeding or pain with a possible pregnancy requires urgent assessment.
Sources and further reading
Last reviewed: 4 September 2026. This page provides general health information and does not replace individual medical assessment or treatment.