The predictive value of antral follicle count remains unchanged across the menstrual cycle.

Objective: To explore whether the predictive value of antral follicle count (AFC) changes when measured at different times during the menstrual cycle. Antimullerian hormone (AMH) and AFC are considered to be equally predictive of poor ovarian response; however, AMH is considered to have an advantage over AFC, because AMH concentrations can be measured at any time during the menstrual cycle. Design(s): Retrospective cohort study. Setting(s): Private IVF clinic. Patient(s): A total of 3,117 patients with a transvaginal ultrasound within 3 months before their first IVF cycle. Intervention(s): None. Main Outcome Measure(s): Receiver operating curves (ROCs) were constructed for AFC as a screening test for poor ovarian response (fewer than four eggs collected). The areas under the curve (AUCs) were compared for ROCs from patients at different phases of the cycle. Result(s): When all patients except those with polycystic ovaries were included, the AUC was 0.79. Further subgroup ROC analyses revealed that the AUCs did not differ significantly when AFC was measured at different phases of the menstrual cycle. Conclusion(s): AFC can be measured regardless of the phase of the menstrual cycle without apparent effect on its predictive value for poor ovarian response. Copyright © 2011 American Society for Reproductive Medicine.