Objective: To compare the hormonal profile when using triptorelin vs. human chorionic gonadotropin (hCG) to trigger ovulation in intrauterine insemination (IUI) cycles.
Study design: Twenty-five patients who underwent 48 cycles were enrolled in a prospective, randomized, crossover study. After ovulation induction with recombinant follicle-stimulating hormone (FSH), couples were randomly allocated to a first cycle with a single dose of 0.2 mg of triptorelin or 5,000 IU of urinary hCG to trigger ovulation; if pregnancy did not occur, a second cycle was carried out, and the patient was crossed over to the other treatment group. Blood was collected the day of hCG/triptorelin administration and both days after IUI.
Results: Patients treated with triptorelin showed a significantly higher FSH and luteinizing hormone (LH) rise 24 hours after the injection when compared to hCG. Serum progesterone was significantly increased 48 hours after hCG administration, although estradiol levels were comparable between the groups.
Conclusion: A higher LH and FSH peak than that induced by hCG was observed. Considering that serum progesterone levels were suboptimal in both protocols and taking into account the lower progesterone production in gonadotropin releasing hormone analogue cycles, corpus luteum supplementation in the luteal phase should be recommended for these patients.