Fixed versus Flexible Gonadotropin Releasing Hormone Antagonist Protocol in Controlled Ovarian Stimulation for Invitro Fertilization in Women with Polycystic Ovary Syndrome

Objective: This study was conducted to compare the results of fixed versus flexible GnRH antagonist protocols in controlled ovarian stimulation for Intra Cytoplasmic Sperm Injection (ICSI) in patients with PCOS. Materials and methods: A randomized clinical trial was performed on 100 PCOS women, who were admitted to a tertiary infertility clinic and were candidate for IVF/ICSI. They were divided into two groups based on the GnRH antagonist protocol. We started GnRH antagonist 0.25mg in flexible protocol when a follicle ≥ 14 mm in diameter was seen in transvaginalsonography (Group 1). In fixed protocol, GnRH antagonist was administered from day 6 of stimulation (Group 2). Number of oocytes in methapase 2, number of developed and frozen embryo as main outcome and days of stimulation, number of gonadotropin and antagonist used assecondry outcome measures were assessed and compared between the two groups. Results: The days of stimulation and the number of antagonist used was not significantly different between fixed and flexible group (p ≥ 0.05).Although the number of gonadotropin injections was significantly lower in flexible group (p = 0.03), the number of oocyte retrieved and the number of embryo which cryopreserved was significantly higher in flexible compared to fixed protocol (p < 0.01). Conclusion: It seems using flexible antagonist protocol in PCOS infertile patients is in favor of better outcomes in terms of number of good quality oocytes and embryo and possibility for cryopreservation for future cycles.