Objective: To compare the effect of twice (split) versus once (single) daily administration of hMG on assisted reproductive technology (ART) cycle parameters.
Design: A randomized clinical trial.
Setting: Hospital-based academic ART program.
Patients: A total of 171 patients undergoing their initial ART cycle were enrolled. All patients received one of two hMG regimens and were excluded from the study if they were receiving medications other than leuprolide acetate (LA) and hMG for ovulation induction.
Interventions: Subjects were randomized to receive an initial dose of 300 IU/d of hMG in either split-dose (i.e., 150 IU twice daily) or single-dose fashion for four successive days after down-regulation with LA. Thereafter, their daily dose was individualized, maintaining a split-or single-dose schedule. All cycles were managed in accordance with our standard ART protocols.
Main outcome measures: Cancellation rate, total hMG requirements, number of days treated with hMG, E2 and P responses, oocyte yield and maturity, fertilization rate, total number of embryos, embryo quality, number of embryos transferred, implantation rate, clinical and ongoing-delivered pregnancy rates.
Results: Split-dose hMG administration resulted in a significantly higher implantation rate, but significantly lower normal and polyspermic fertilization rates than single-dose hMG administration. No significant differences were noted between the two dosage protocols with respect to the other outcome measures.
Conclusions: Split-dose hMG administration may be associated with significantly higher implantation rates; single-dose hMG with significantly higher fertilization rates. Although our data also demonstrate a trend toward higher clinical and ongoing-delivered pregnancy rates with split-dose therapy, demonstration of a significant difference would require a multicenter trial. Based on our data, clinicians may want to consider split-dose therapy for patients with repeated implantation failures.