Urinary Gonadotropins as Markers of Puberty in Girls and Boys During Late Childhood and Adolescence: Evidence From the SCAMP Cohort.

INTRODUCTION: Urinary gonadotropins measurement is a noninvasive method for evaluation of pubertal development and may have utility in population studies. OBJECTIVES: To investigate the utility of urinary gonadotropins as a noninvasive biomarker of puberty in boys and girls. METHODS: School-based adolescent cohort study with two time points for collecting school time urine samples and self-reported assessment of puberty through the Pubertal Development Scale (PDS) approximately 2 years apart. FSH and LH were measured by two-site sandwich immunoassay and corrected for creatinine excretion. RESULTS: A total of 941 samples from 741 girls and 1198 samples from 899 boys aged between 11 and 16 years were analysed. Samples were collected at a median age of 12.3 years (range 11.1, 13.2) and 14.2 years (13.4, 15.7). The annual change for uLH:FSH ratio was +0.028 (95% [0.021, 0.035]) and +0.035 (95% [0.027, 0.043]) in girls and boys, respectively. In a subgroup analysis of 59 samples from girls and 233 samples from boys, collected within 90 days of a PDS, were analysed for correlations with self-reported pubertal development. In girls, uLH:FSH ratio showed positive correlations with self-report breast development (r = 0.29), self-report menarchal status(r = 0.35), composite PDS score (r = 0.39) and PDS-derived pubertal categories (r = 0.45). In boys, uLH:FSH revealed negligible correlations with self-reported pubertal development, PDS composite score and PDS-derived pubertal categories. CONCLUSIONS: An increase in urinary LH:FSH ratio is associated with an increase in self-reported pubertal development in adolescent girls and represents a valid noninvasive biomarker of puberty in population studies.