Flexible GnRH antagonist protocol versus GnRH agonist long protocol in patients at high risk of ovarian hyperstimulation syndrome: a prospective randomized controlled trial

Abstract

OBJECTIVE: To compare the flexible GnRH antagonist and the GnRH agonist long protocol in patients at high risk of OHSS undergoing IVF.DESIGN: Single-centre open label randomized prospective study.MATERIALS AND METHODS: The study included 144 women who had moderate or severe OHSS or had been at risk of OHSS during their first IVF/ICSI cycle with a mid-luteal long GnRH agonist plus gonadotrophin stimulation protocol. Patients were randomized to receive either cetrorelix 0.25 mg/day starting on day 3 of the menstrual cycle (antagonist group) or triptorelin 0.1 mg/day starting on day 21 of the menstrual cycle (agonist group). Ovarian stimulation was achieved with rFSH initiated on day 3 of the cycle at the maximal dose of 150 IU; the dose was adjusted depending on ovarian response. Embryo transfer was performed 2 or 3 days after oocyte retrieval. Luteal phase support was started on the day of oocyte retrieval using micronised progesterone vaginal gel.RESULTS: The two groups were similar in mean age, duration of infertility, body mass index, baseline FSH, total amount of rFSH administered and proportion of patients undergoing intracytoplasmic sperm injection. When oocyte maturation was triggered, the levels of E2 were lower in the antagonist group than in the agonist group (p<0.001). The number of cancelled cycles was significantly higher in the GnRH agonist group than in the GnRH antagonist group (9 versus 1, p=0.022). The total number of oocytes retrieved, the number of metaphase II oocytes retrieved and the fertilization rate were similar in the two groups (p=0.602, p=0.621 and p=0.946). Clinical pregnancy rate per initiated cycle was similar in the the two groups (p=0.457); live birth rate per initiated cycle was 23.6% in the antagonist group and 26.4% in the agonist group (p=0.700).CONCLUSION: When compared with the GnRH agonist protocol, the flexible GnRh antagonist protocol is associated with a similar pregnancy rate with a reduction in the number of cycles cancelled because of the risk of OHSS. OBJECTIVE: To compare the flexible GnRH antagonist and the GnRH agonist long protocol in patients at high risk of OHSS undergoing IVF. DESIGN: Single-centre open label randomized prospective study. MATERIALS AND METHODS: The study included 144 women who had moderate or severe OHSS or had been at risk of OHSS during their first IVF/ICSI cycle with a mid-luteal long GnRH agonist plus gonadotrophin stimulation protocol. Patients were randomized to receive either cetrorelix 0.25 mg/day starting on day 3 of the menstrual cycle (antagonist group) or triptorelin 0.1 mg/day starting on day 21 of the menstrual cycle (agonist group). Ovarian stimulation was achieved with rFSH initiated on day 3 of the cycle at the maximal dose of 150 IU; the dose was adjusted depending on ovarian response. Embryo transfer was performed 2 or 3 days after oocyte retrieval. Luteal phase support was started on the day of oocyte retrieval using micronised progesterone vaginal gel. RESULTS: The two groups were similar in mean age, duration of infertility, body mass index, baseline FSH, total amount of rFSH administered and proportion of patients undergoing intracytoplasmic sperm injection. When oocyte maturation was triggered, the levels of E2 were lower in the antagonist group than in the agonist group (p<0.001). The number of cancelled cycles was significantly higher in the GnRH agonist group than in the GnRH antagonist group (9 versus 1, p=0.022). The total number of oocytes retrieved, the number of metaphase II oocytes retrieved and the fertilization rate were similar in the two groups (p=0.602, p=0.621 and p=0.946). Clinical pregnancy rate per initiated cycle was similar in the the two groups (p=0.457); live birth rate per initiated cycle was 23.6% in the antagonist group and 26.4% in the agonist group (p=0.700). CONCLUSION: When compared with the GnRH agonist protocol, the flexible GnRh antagonist protocol is associated with a similar pregnancy rate with a reduction in the number of cycles cancelled because of the risk of OHSS.