After prospective randomized phase III studies comparing GnRH antagonist protocols with GnRH agonist long protocols were published in 2000–2001 [20], GnRH antagonist protocols came to be used more frequently in clinics in a wide range of patients, including patients with normal ovarian responses as well as patients with poor or high responses; this last group includes patients with PCOS. This evidence concerns the gene GNRH1 and polycystic ovary syndrome.