Abstract

Background: The median age at thelarche in Thai girls has decreased from 10.3 to 9.4 years over the last 20 years. An age at thelarche of 7.0–9.0 years, which is earlier than in the general population, is considered as early puberty.

Objective: To study the pattern of pubertal development in Thai girls with early puberty.

Study design: A total of 104 girls with breast development at 7.0–9.0 years who attended Songklanagarind Hospital between 2003 and 2005 were followed up until they attained their near-final height (NFH).

Results: The mean age at initial evaluation was 8.5±1.0 years. The average age at menarche and on attaining NFH was 10.2±0.9 and 12.6±0.4 years, respectively. The average NFH was 154.0±4.9 cm, which was similar to the target height of 153.1±4.8 cm. Comparison of girls who were normal weight and obese (weight-for-height >120%) revealed that the latter had an earlier age at menarche (9.8±0.8 vs. 10.5±0.8 years, p<0.01) and reached their NFH at a younger age (12.2±0.4 vs. 12.9±0.4 years, p=0.02). However, normal-weight and obese girls reached approximately the same NFH (155.8±4.8 vs. 153.1±4.0 cm, p=0.058).

Conclusion: Girls with early puberty attained NFH similar to their genetic potential. Obese girls attained NFH at an earlier age and had the same NFH as normal-weight girls.