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Fixed versus flexible gonadotropin-releasing hormone antagonist administration in in vitro fertilization: a
Efstratios M Kolibianakis1, Christos A Venetis, Lydia Kalogeropoulou
1Unit for Human Reproduction, First Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
Objective:
To evaluate whether the incidence of luteinizing hormone (LH) rise is reduced by using a flexible compared with a fixed day-6 protocol of GnRH antagonist administration.
Design:
Randomized controlled trial.
Setting:
Tertiary university hospital.
Patient(S):
Patients undergoing in vitro fertilization (n = 146).
Intervention(S):
Ovarian stimulation was performed using recombinant FSH and GnRH antagonists. GnRH antagonist cetrorelix (0.25 mg/d) was started either on day 6 of stimulation (fixed group) or when LH was >10 IU/L, and/or a follicle with mean diameter >12 mm was present, and/or serum E(2) was >150 pg/mL. Patient monitoring was initiated on day 3 of stimulation.
Main Outcome Measure(S):
Incidence of LH rise.
Result(S):
No statistically significant difference was observed between the flexible and fixed groups regarding the incidence of LH rise, which was lower in the flexible group (11.0% vs. 15.1%, difference -4.1%, 95% confidence interval -15.4% to +7.1%). No LH surges were observed in any of the patients studied.
Conclusion(S):
Flexible antagonist administration from day 3 onward does not appear to reduce the incidence of LH rises compared with fixed antagonist administration on day 6 of stimulation.
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