group of rats with letrozole-induced PCOS (PCOS + EC500) showed obvious changes in the developed follicles, and there was some indication of ovarian aromatase, Ar and Erβ expression in the granulosa cells of the follicle antrum; this effect was most notable in the PCOS + EC500 group. Here, CYP19A1 is linked to polycystic ovary syndrome.