OBJECTIVE: To assess the prevalence of anemia (hemoglobin level <12g/dL) in adolescents, according to their sexual maturation stage. METHODS: A cross-sectional study was conducted with all adolescents enrolled in 5th - 8th grades in a private school in the city of São Paulo. Their hemoglobin level was measured (using Hemocue®) and sexual development was self-evaluated (with the aid of pictures of the maturation stages proposed by Tanner). The social indicators evaluated were the per capita family income and maternal schooling. Student t test and non-parametric Kruskal-Wallis test were used for mean comparison and Chi-square-test for associations (p<0.05). RESULTS: We analyzed 118 students, of which 66.9% were females (aged 12.2±1.13 years) and 33.1% were males (aged 12.0±1.18 years). The mean hemoglobin level was 13.2±1.08 g/dL for females and 13.3±1.21 g/dL for males, with no significant difference. An apparent increase in the mean hemoglobin level was verified along with sexual development of the adolescents. Anemia was detected in 11% of them, most in the pubertal stage, which is classified by the World Health Organization as ''mild prevalence''. No association was found between social indicators and anemia prevalence. CONCLUSION: This study showed low prevalence of anemia at rates higher than expected during puberty in a private school and indicates a trend for increased hemoglobin levels in connection with sexual development of adolescents. Further studies on anemia prevalence should be carried out to establish the factors associated with this disease, having adolescents from different socioeconomic levels as subjects.
anemia; hemoglobin levels; puberty; sexual maturation; adolescence
