P–644 Effect of a reduced dose of long-acting gonadotropin releasing hormone (GnRH) agonist versus short-acting GnRH agonist on pregnancy outcome in patients undergoing ICSI/ET cycles

Abstract

Study question Are pregnancy outcome different between reduced dose of long-acting GnRH agonist and short-acting GnRH agonist in patients undergoing ICSI/ET cycles? Summary answer Clinical outcomes were not significantly different between the two group. What is known already There is no consensus on which of two GnRH agonist protocol is the most effective form and it has been challenging which one improves the clinical pregnancy rate. Study design, size, duration This is randomized clinical trial that 394 patients, who were candidates for ICSI/ET, were included in this study between April 2019 and January 2020. Participants/materials, setting, methods Patients were randomly divided into two groups using blocks of 8; hereby every 8 subjects were randomized, four were allocated to the long-acting GnRH agonist, and four were allocated to the short-acting GnRH agonist randomly. Main results and the role of chance No significant difference was noted between the two groups in progesterone and estradiol levels at hCG administration day. Despite no significant difference between the two groups in ART outcomes, interestingly rate of ovarian hyperstimulation syndrome (OHSS) occurrence was significantly higher in the short-acting group (P = 0.005). Limitations, reasons for caution We couldn’t evaluate the long-term consequence of pregnancy including live birth rate and effect of GnRH analogue on fetus. Wider implications of the findings: A lower rate of OHSS occurrence in the long-acting group, and similar ART outcomes in both groups. Trial registration number IRCT20190609043845N1