SHBG and polycystic ovary syndrome: In fact, it is well known from PCOS studies that IR and hyperinsulinemia influenced fertility and conception, enhancing androstenedione and testosterone production, reducing SHBG levels, increasing free testosterone levels, stopping follicles growth, influencing pituitary gland sensitivity to GnRH, and stimulating pituitary LH release (Shaaban et al., 2021).