Rebato E, Rosique J, González Apraiz A
Departamento de Biología Animal y Genética (Antropología), Universidad del País Vasco, Bilbao, Spain.
Anthropol Anz. 1994 Jun;52(2):143-8.
Reported data on age at menarche in a sample of Biscayan schoolgirls are compared with data from several Spanish populations. Though the mean age falls in the range of variation of the Spanish means, the analysis of variance shows significant differences among the series. With regard to the possible secular trend of this event in the Biscay province, both a stability of menarcheal age and a diminution of the process of variability are observed.