PRL and polycystic ovary syndrome: Human ovarian follicular cells and fluids (FF; Supplementary Table 2) were collected from lean PCOS (based on Rotterdam criteria; BMI<30) and non-PCOS subjects (premenopausal, 18-40 years) with normal thyroid function and prolactin levels, undergoing assisted reproduction treatment at the CReATe Fertility Centre, Toronto, Canada.