Preschool stunting, age at menarche and adolescent height: a longitudinal study in rural Senegal.

OBJECTIVE: To study the impact of preschool stunting on adolescent height and age at menarche in rural West Africa. DESIGN: A longitudinal, population-based study. SETTING: The Niakhar study area in Central Senegal. SUBJECTS: 1650 children aged 12-17 y with known height-for-age at the age of 2-5 y. MAIN OUTCOME MEASURES: Adolescent height; mean age at menarche of girls estimated by the status quo method. RESULTS: The subjects were divided into three groups of preschool height-for-age: < -2, -2 to -1 and > -1 z-score of the NCHS reference. The mean height during adolescence differed significantly according to preschool height-for-age for both boys and girls (P < 0.001). Relative risk of adolescent stunting according to preschool stunting varied from 2.0-4.0 depending on age and sex. Estimated mean age at menarche was 17.2 (95% fiducial confidence interval: 16.6-18.7), 16.5 (16.1-17.2) and 15.6 (15.2-16.0) y, respectively, for the three groups of preschool height-for-age (P < 0.001). Mean increment from age 5 y to adolescence did not differ significantly among the boys according to preschool stunting, but among the girls aged 16-17 y, the increment was higher for those who had been stunted during preschool life (P < 0.01). CONCLUSION: Some evidence of catch-up growth between the ages of 5 and 17 y was found for stunted girls. The significant delay in sexual maturation of the stunted girls suggests that stunted children of both sexes have a possibility of catch-up growth after the age of 17 y.