A Modified Ultra-long Down-regulation Protocol Improved Endometrial Receptivity and Clinical Outcome for Infertile Patients with Poly-cystic Ovarian Syndrome

Objectives: There are various ovarian stimulation protocols for in vitro fertilization (IVF). Particularly for Poly-cystic Ovarian Syndrome (PCOS) patients an optimized protocol of pituitary FSH and LH down regulating gonadotropin-releasing hormone agonist (GnRHa) medication without complications is still a challenge. Methods: We retrospectively compared the primary endpoint of an ultra-long and a conventional long GnRHa protocol for intracytoplasmic sperm injection (ICSI)/ IVF treatments of PCOS patients with several clinical indexes. Results: In our modified ultra-long protocol group, the endometrial thickness, morphology and blood flow were significantly optimized compared to the conventional long protocol. The serum progestogen (P) concentrations and P/E2 (P*1000/estrogen (E2)) ratio on the day of human chorionic gonadotrophin (HCG) administration were significantly decreased in the modified ultra-long down-regulation protocol, while the pregnancy and implantation rates were significantly higher. There were no significant differences in the average number of obtained oocytes, good quality embryo rates, cancel rates, fertilization rates, abortion rates, serious ovarian hyperstimulation syndrome (OHSS) incidences, ectopic pregnancy rates as well as gonadotrophin (Gn) dosages between two groups. Conclusion: The modified ultra-long protocol plus human menopausal gonadotropin (hMG) medication was superior to the long protocol and leading to better implantation as well as pregnancy outcomes for infertile PCOS patients.