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Updated: Jul 11, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Controlled ovarian hyperstimulation using multi-dose gonadotropin-releasing hormone (GnRH) antagonist results in less
Raoul Orvieto1, Michael Volodarsky, Eduard Hod
1Department of Obstetrics and Gynecology, Barzilai Medical Center, Ashkelon, Israel. raoulo@barzi.health.gov.il
Objective:
The aim of the study was to investigate whether controlled ovarian hyperstimulation (COH) using multi-dose gonadotropin-releasing hormone (GnRH) antagonist results in a lesser degree of systemic inflammation than the GnRH-agonist long protocol.
Design:
Prospective, observational study.
Patients And Methods:
Blood was drawn three times during the COH cycle from patients undergoing the long GnRH-agonist protocol (agonist group) (n = 12) or the multi-dose GnRH-antagonist protocol (antagonist group) (n = 15): the day on which adequate suppression was obtained (agonist group), or day 2 or 3 of the menstrual cycle and before gonadotropin treatment (antagonist group) (Day-0); the day of or prior to administration of human chorionic gonadotropin (Day-hCG); and the day of ovum pick-up (Day-OPU). Levels of sex steroids and serum C-reactive protein (CRP) were compared between the two study groups among the three time points.
Results:
While no between-group differences were observed in patient age or ovarian stimulation characteristics, a significantly higher number of oocytes were retrieved in the antagonist compared with the agonist group. In both groups, serum CRP levels were significantly higher on Day-OPU than on Day-hCG and Day-0. While serum CRP levels were higher on Day-hCG than Day-0, the difference was statistically significant only for the agonist group (p < 0.05). Moreover, Day-OPU serum CRP levels were significantly higher in the agonist than in the antagonist subgroup.
Conclusion:
COH using the multi-dose GnRH-antagonist protocol yields a lesser degree of systemic inflammation, as reflected by CRP levels, than the GnRH-agonist long protocol.
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