Higher than usual insulin levels in the blood.
Why it matters for PCOS
Insulin is the hormone that helps cells take up glucose from the blood. When the body becomes less sensitive to insulin (insulin resistance), the pancreas releases more insulin to compensate, which leads to hyperinsulinaemia. This is common in PCOS, although it does not affect every woman.
High insulin levels can raise androgen production by the ovaries and lower SHBG, the protein that binds hormones. These effects can contribute to irregular cycles and androgen signs such as acne and hirsutism in some women. Hyperinsulinaemia is not part of the PCOS diagnostic criteria, and a doctor reads it alongside other test results and your overall clinical picture.
This glossary is education, not diagnosis. For your own situation, ask a doctor or pharmacist.