Simultaneous evaluation of basal follicle-stimulating hormone and 17β-estradiol response to gonadotropin-releasing hormone analogue stimulation: an improved predictor of ovarian reserve

Abstract

Objective: To compare different predictors of ovarian reserve. Design: Prospective study. Setting: The Assisted Conception Unit, University College London Hospitals. Patient(s): One hundred seventy-seven patients undergoing IVF treatment. Intervention(s): Blood samples were collected on cycle day 2 to determine basal levels of FSH and 17β-E 2 and the FSH/LH ratio, and on cycle days 3 and 4 to assess the increase in FSH (ΔFSH) and 17β-E 2 (ΔE 2) after the commencement of GnRH analogue (GnRH-a) stimulation. Ultrasound scans were performed during ovarian stimulation to assess the number of follicles. Main Outcome Measure(s): Day 2 FSH and 17β-E 2 levels, the FSH/LH ratio, and the ΔFSH and ΔE 2 after the commencement of GnRH-a stimulation were correlated with the number of follicles obtained after ovarian stimulation. Result(s): All the possible predictors considered, except for the day 2 E 2 level and the ΔFSH, correlated significantly with the ovarian response. The best single correlation was between the number of follicles and the ΔE 2 (GnRH-a test). When the FSH level was evaluated simultaneously, the correlation was strengthened, resulting in a better negative predictive value. Conclusion(s): Simultaneous evaluation of basal levels of FSH and of the response of E 2 to GnRH-a stimulation seems to be the best marker of ovarian reserve and a sensitive predictor of response to ovarian stimulation in patients undergoing IVF treatment.