Purpose: To compare pregnancy rates in GnRH-antagonist cycles triggered with hCG after luteal phase support with intranasal GnRH agonist as sole luteal phase support versus standard vaginal progesterone preparation.Methods: Prospective randomized controlled study of patients who underwent antagonist-based IVF cycles triggered with hCG at university-a liated tertiary medical center between 2020 and 2022. Patients meeting the inclusion criteria were randomly assigned to either intranasal GnRH-agonist or vaginal progesterone for luteal phase support. Pregnancy rates were the main outcome compared between the two study groups.Results: A total of 150 patients underwent 164 cycles, 127 cycles of which were included in the study cohort. Of them, 64 (50.4%) and 63 (49.6%) cycles were treated with GnRH-agonist or progesterone respectively as sole luteal phase support. A signi cantly higher pregnancy rate was demonstrated in the GnRH-agonist group compared with the progesterone group. After adjustment of several potential confounders such as age, body mass index, past obstetric history, number of IVF cycles, oocyte retrieved and embryos transferred, GnRH-agonist was still associated with a higher pregnancy rate (odds ratio 3.4, 95% con dence interval 1.4-8.3). Ovarian hyperstimulation syndrome rates were similar between the groups.Conclusions: This prospective study suggests that nasal GnRH-agonist for luteal phase support is associated with higher pregnancy rates compared with standard progesterone support in an antagonistbased protocol triggered with hCG, while maintaining a similar safety pro le.
HighlightsTo the best of our knowledge, this is the rst prospective randomized study to compare between pregnancy rates of patients treated with repeated intranasal GnRH-a versus progesterone as sole LPS following GnRH-ant-based cycles triggered with hCG. Our ndings suggest that intranasal GnRH-a administration as a sole luteal support in antagonist-based IVF cycles triggered with hCG results in improved pregnancy rates in comparison with traditional irritating vaginal preparations, giving ART caregivers another medical option and further personalizing reproductive medicine.