Which is thought to suppress the secretion of pituitary Gn, inhibit premature of LH surge, avoid premature follicular luteinisation and improve oocyte quality, while facilitating synchronization of follicular development and increasing the number of oocyte gained, thus improving clinical pregnancy rates.[13] Due to the special characteristics of endocrine disorder, most PCOS women have a good ovarian response after controlled ovulation with long GnRH-a protocol. This evidence concerns the gene PLOD1 and endocrine system disorder.