Objective—To compare cycle outcomes among normal responding patients ≤30 years receiving microdose follicular flare (MDF) and long-luteal agonist (LL). Design—Retrospective cohort study. Setting—Military-based ART center. Patients—First, autologous ART cycles among 499 women ≤30 years old from 01/1999 to 12/2005. Interventions—Following OCP administration prior to cycle start, patients were non-randomly assigned to either LL or MDF for LH surge suppression. LL received 1 mg/d leuprolide acetate (LA) on cycle day 21, which was reduced to 0.25 mg/day 10–14 days later. MDF received LA (40 μg BID) beginning 3 days after discontinuing OCPs. Both groups received a combination of hMG and rFSH. Main Outcome Measures—Primary outcomes were implantation, clinical pregnancy and live birth rates; in cycle variables included peak E2, oocytes retrieved, oocyte maturity, and fertilization rate. Results—Multivariable models controlling for confounding by treatment indication found no significant differences between groups in implantation (MDF:36%; LL:38%), clinical pregnancy