Early luteal phase endocrine profile is affected by the mode of triggering final oocyte maturation and the luteal phase support used in recombinant follicle-stimulating hormone-gonadotropin-releasing hormone antagonist in vitro fertilization cycles.

Objective: To assess endocrine differences during early luteal phase according to mode of triggering final oocyte maturation with or without luteal phase support (LPS).

Design: A prospective randomized study.

Setting: University center for reproductive medicine.

Patient(s): Four oocyte donors each underwent four consecutive cycles.

Intervention(s): To avoid interpatient variation, each donor underwent the same stimulation regimen. However, different modes of triggering final oocyte maturation and LPS were administered: A) 10,000 IU hCG and standard LPS; B) GnRH agonist (GnRHa; 0.2 mg triptorelin), and 35 hours later 1,500 IU hCG, and standard LPS; C) GnRH agonist (0.2 mg triptorelin) and standard LPS; and D) GnRH agonist (0.2 mg triptorelin) without LPS.

Main Outcome Measure(s): Blood sampling was performed on the day of ovulation trigger, ovulation trigger + 1 day, and ovum pick-up + 5 days. Serum E2, FSH, LH, and P were measured.

Result(s): The early luteal phase steroid levels following GnRHa trigger and modified luteal phase support (B) were similar to those seen after hCG trigger (A). However, significant differences were seen between groups A and B compared with C and D, as well as between groups C and D.

Conclusion(s): Administration of a single bolus of GnRHa effectively induced LH and FSH surges in oocyte donors stimulated with recombinant FSH and cotreated with a GnRH antagonist. However, gonadotropin and steroid levels differed significantly according to the type of luteal phase support used after GnRHa trigger.

European Community Clinical Trial System (eudract) Number: 2009-009429-26.