Later, progestin-primed ovarian stimulation (PPOS) protocol was revealed to be effective and safe for suppressing premature LH surge and also showed similar oocyte yields and pregnancy outcomes compared with conventional short protocol [6, 7], which has been applied in normally ovulating women, poor responders, and polycystic ovarian syndrome (PCOS) [6, 8–10]. Here, PLOD1 is linked to polycystic ovary syndrome.