A prospective, randomized study comparing morning to evening administration of gonadotropins in ART.

Objective: We sought to determine whether administering the daily gonadotropin dose in the morning (AM) or in the evening (PM) affects cycle outcome in patients undergoing IVF.

Design: This is a prospective randomized study.

Setting: The study is performed in a private assisted reproductive technology (ART) clinic.

Patient(s): The study included one hundred and twenty-seven women undergoing IVF.

Intervention(s): Morning (AM) and evening (PM) administration of gonadotropins (uFSH and hMG) was compared.

Main Outcome Measure(s): Live birth rate was the main outcome measured. Secondary outcomes including total IU use, days of stimulation, peak E, peak P, endometrial thickness, number of oocytes retrieved, MII oocytes, fertilization rates, #ET, IR, and clinical PR were all assessed.

Results: A total of 127 cycles were included, 61 in the AM group and 67 in the PM group. Baseline and stimulation characteristics were similar in both groups. There was a trend for a higher implantation rate in the AM group vs. the PM group (60.3 vs. 47.2%, P = 0.066). The AM group had a higher chemical pregnancy rate compared to the PM group (81.7 vs. 65.6%, P = 0.024) and a higher clinical pregnancy rate (78.3 vs. 62.1%, P = 0.048), but the delivery rates were similar (68.3 vs. 56.1%, P = 0.16). The study was unfortunately prematurely terminated when uFSH (Bravelle©) was pulled out of the US market.

Conclusions: AM administration of gonadotropins may be associated with a better ART outcome compared to PM administration. Larger studies are needed to confirm our findings.