In PCOS patients, follicle monitoring and timed intercourse have been shown to increase treatment success after initiation of OI.16 CC leads to depletion of estrogen receptors, and this effect is prolonged because of its long half-life.17 This depletion causes endometrial thinning and adversely changes the quality of cervical mucus. The gene discussed is ESR1; the disease is polycystic ovary syndrome.