Yes, prolonged and/or heavy periods are common (but less talked about) symptoms of PCOS. The hormonal imbalance in PCOS can lead to irregular ovulation or anovulation (lack of ovulation). When ovulation doesn't occur regularly, the body may not produce enough progesterone, which can result in the uterine lining not shedding completely during menstruation. This can lead to heavier or more prolonged periods.
The elevated levels of androgens (male hormones) in PCOS can also contribute to the growth of the endometrial lining, leading to increased tissue that needs to be shed during menstruation, potentially causing heavier bleeding.