PLOD1 and polycystic ovary syndrome: Hormonal studies in women with PCOS have revealed elevated levels of testosterone and estrogen, demonstrating an increased ratio of luteinizing hormone (LH) to follicle-stimulating hormone (FSH), as well as higher concentrations of estrone compared to estradiol, and androstenedione levels that are at the upper limits of normal or elevated (Casanova et al., 2019).