The need to step up the gonadotropin dosage in the stimulation phase of IVF treatment predicts a poor outcome.

Purpose: It is a common practice to increase the gonadotropin dose during ovarian stimulation when the estradiol (E2) rise is found to be inadequate. The prognostic impact of the use of this step-up regimen on the outcome of the affected in vitro fertilization (IVF) cycle is the subject of this study.

Methods: This is a retrospective analysis of IVF cycles in a series of consecutive patients who required an increase in the gonadotropin dosage during the stimulation phase because of inadequate E2 rise. Controls consisted of patients in whom the dose was not increased. After 4 days of stimulation, the gonadotropin dosage was increased if E2 levels failed to rise by 70% every 2 days. Outcome was defined in terms of maximum E2 level, number of follicles at aspiration, number of oocytes obtained, fertility rate, and pregnancy rate and was compared in study and control patients. Pregnancy was defined by sonographic demonstration of cardiovascular activity.

Results: One hundred forty-five patients were analyzed. A step-up regimen was used in 35 patients (24.1%). Patients who required the step-up dosing had significantly lower peak E2 levels (1373 vs 1828 pg/ml; P < 0.005), fewer follicles measuring greater than 16 mm (7.2 vs 9.7; P < 0.003), and fewer oocytes recovered (8.3 vs 11.2; P < 0.009). The fertilization rate (67.6 vs 64.2%) was not significantly different. The pregnancy rate (8.5 vs 32.7%; P < 0.004) was significantly lower in the group requiring the step-up regimen.

Conclusions: The utilization of a step-up regimen during an IVF treatment cycle is a predictor of a poor outcome for the specific IVF cycle. As this information is available before retrieval, consideration of cycle cancellation may be appropriate.