The cohort of antral follicles measuring 2–6 mm reflects the quantitative status of ovarian reserve as assessed by serum levels of anti-Müllerian hormone and response to controlled ovarian stimulation

ObjectiveTo evaluate the relationship between serum anti-Müllerian hormone (AMH) and antral follicle size, and to ascertain which cohort of antral follicles is most predictive of the response to controlled ovarian stimulation during assisted reproduction treatment (ART).DesignProspective study.SettingUniversity-based Assisted Conception Unit.Patient(s)One hundred thirteen women undergoing first cycle of ART.Intervention(s)Transvaginal 3D-ultrasound assessment and venipuncture in the early-follicular phase of the menstrual cycle.Main Outcome Measure(s)Serum AMH levels, number of mature oocytes retrieved and poor ovarian response.Result(s)The antral follicle cohorts measuring 2 to 3 mm, >3 to 4 mm, >4 to 5 mm, and >5 to 6 mm were most significantly correlated with AMH (r = .30, .27, .30, and .41, respectively) and the number of mature oocytes retrieved (r = .28, .23, .29, and .34, respectively). Although these follicle cohorts of 2-6 mm were significant predictors of the number of mature oocytes retrieved on regression analysis, their discriminative ability (area under the curve [AUC]: 0.829) for the prediction of poor ovarian response was similar to total counts made using cohorts of 2 to 4 mm, 2 to 5 mm, 2 to 8 mm, and 2 to 10 mm (AUCs: 0.794, 0.812, 0.852, and 0.826, respectively).Conclusion(s)The number of antral follicles measuring 2 to 6 mm is most reflective of the quantitative ovarian reserve. However, the ability of this group of antral follicles to predict poor ovarian response appears similar to that of the follicular cohorts of 2 to 4 mm, 2 to 5 mm, 2 to 8 mm, and 2 to 10 mm.