Esteves SC, Yarali H, Vuong LN, et al. - Researchers aimed at determining the agreement between antral follicle count (AFC) and anti-Müllerian hormone (AMH) levels when employed to classify patients according to the Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria. In this population-based cohort study, 9,484 consecutive patients were included who underwent treatment in three fertility clinics in Brazil, Turkey and Vietnam between 2015 and 2017. Classification of a total of 73.8% of individuals was done under the same group using both biomarkers. As per findings, the AFC and the AMH levels show a strong agreement in classifying POSEIDON patients; hence, for this purpose, either of the two can be employed, although one in four women will have discordant values when both biomarkers are utilized.