Purpose: to evaluate whether the duration of gonadotropin stimulation predicts the likelihood of live birth after ART.
Methods: all IVF or ICSI cycles using fresh autologous oocytes at our institution between January 2004 and December 2007 were analyzed.
Results: out of 699 cycles resulting in oocyte retrieval, 193 produced a live birth (27.6%). Women who achieved a live birth had a significantly shorter stimulation phase (11.1 vs. 11.5 days, respectively). Multivariable analysis suggested that 13 days or longer of stimulation decreased the likelihood of a live birth by 53% as compared to cycles that were 10-12 days long (odds ratio [OR] 0.47; 95% confidence interval [CI]: 0.30-0.75) after adjustment for female age, maximum historical FSH, total dose of gonadotropin received, oocytes retrieved, embryos transferred, antagonist suppression and PCOS diagnosis.
Conclusions: prolonged duration of gonadotropin stimulation is an independent negative predictor of ART success in our cohort.