In a study of girls with CPP, Hagen et al. used the same assay as the present study and reported a median plasma AMH concentration of 20.3 pmol/L in 13 girls with CPP and 2 girls with advanced puberty before GnRH analog treatment, values similar to those of age-matched controls (23 pmol/L) and Tanner stage-matched controls (19 pmol/L) [6]. This evidence concerns the gene GNRH1 and central precocious puberty.