An oocyte is the female egg cell that matures inside an ovarian follicle.
Why it matters for PCOS
An oocyte is the egg cell that develops inside an ovarian follicle, and once mature it is released at ovulation to be potentially fertilised. In PCOS, hormonal imbalance causes many small follicles to stall early, so the oocytes inside them do not mature fully and ovulation becomes irregular or stops. This is a main reason PCOS can affect fertility even though the follicle count looks high on ultrasound.
In fertility treatments such as IVF, mature oocytes are collected from the ovaries to be fertilised in the lab. The number and maturity of oocytes can only be judged by a specialist through monitoring, not from symptoms alone.
This glossary is education, not diagnosis. For your own situation, ask a doctor or pharmacist.