Comparison Between Chronological and Bone Age at Menarche in Girls with Laron Syndrome.

Background: In the literature, the occurrence of menarche, the index of female sexual maturation, is related to chronological age (CA), but in conditions of abnormal growth it was proposed that determination of bone age (BA) was a better index of pubertal maturation than CA. Aim: To compare CA with BA at menarche in girls with Laron Syndrome (LS), a model of genetic IGF-I deficiency, which causes severe dwarfism and delayed puberty. Subjects: Data were retrieved retrospectively from our medical records. Nine untreated and four IGF-I-treated girls with LS were included in the study. Eleven GH-treated girls with congenital isolated GH deficiency (cIGHD) served as comparison. Results: The mean BA at menarche of untreated LS patients (13.4 y) was 0.7 y less than the CA (14.1 y), and the mean BA of IGF-I-treated girls (13.7 y) was 1.2 y less than the CA (14.9 y). Body height and weight did not influence the age at menarche. Conclusion: In girls with LS, the determination of BA seems a more useful index of female pubertal maturation than CA.