[Influence of the age at the start of pubertal growth on adult height]. / Influencia de la edad de inicio del brote de crecimiento puberal en la talla adulta.

ABSTRACT

BACKGROUND AND OBJECTIVE: In both sexes, postnatal growth differs among subjects due to differences in age at which pubertal growth begins. However, little is known on the influence of this fact on normal adult height distribution. Our aim was to compare adult height reached in the 5 maturing groups, according to age at pubertal onset. SUBJECTS AND METHOD: Two-hundred and thirty healthy subjects (115 girls, and 115 boys) were followed longitudinally by 2 pediatricians from birth to adult height. Height was evaluated 1-3 times/year and the corresponding growth chart was made. Growth velocity (cm/year), age at pubertal growth start, pubertal growth gain, age at adult height and adult height were recorded for each subject. According to the age at start of pubertal growth, subjects were distributed in 5 maturing groups 8-9 years (n = 10), 9-10 years (n = 29), 10-11 years (n = 45), 11-12 years (n = 23) and 12-13 years (n = 8) in girls, and 10-11 years (n = 10), 11-12 years (n = 26), 12-13 years (n = 45), 13-14 years (n = 27) and 14-15 years (n = 7) in boys. RESULTS: In both sexes, statistically-significant differences (p < 0.01) were found for mean height values at start of pubertal growth and for mean total pubertal height gain values (p < 0.0001) when the 5 maturing groups were compared among themselves. However, such differences were not found when mean adult height values were compared among the 5 groups or when these values were compared with adult height values obtained in other recent Spanish longitudinal and cross-sectional growth studies. A statistically-significant correlation (p growth and adult height. However, this was not found for age at the start of pubertal growth and adult height.

CONCLUSIONS:

In both sexes, genetic factors, and not the time when pubertal growth begins, influenced adult height. Although the duration of postnatal growth is shorter in earlier than in later maturers, the former gain more centimetrers during pubertal growth and reach similar adult height.