TY - JOUR

T1 - Sex-independent timing of the onset of central puberty revealed by nocturnal luteinizing hormone concentrations

AU - Demir, And

AU - Hero, Matti

AU - Juul, Anders

AU - Main, Katharina M.

N1 - Publisher Copyright: © 2023 The Authors. Clinical Endocrinology published by John Wiley & Sons Ltd.

PY - 2023

Y1 - 2023

N2 - Objective: We designed a longitudinal study to investigate the association between the ages of central pubertal activation and the appearance of clinical signs of puberty and determined total luteinizing hormone (LH) immunoreactivity in daytime- and nocturnal sleeptime-excreted urine samples. Patients and Measurements: Thirty healthy volunteers (17 boys and 13 girls, aged 3.4–15.2 years and 4.3–14.3 years, respectively, at the beginning of the study) were included. Male and female subjects were followed for an average of 15 visits during 5.5 and 5.8 years on average, respectively. At each visit, subjects provided 24-h urine samples divided into nocturnal sleeptime and waketime portions according to the participant's sleep-and-wake rhythm. Total urinary LH (U-LH) concentrations were measured in duplicate by Delfia® IFMA (Wallac), which has been designed specifically to detect intact LH as well as the beta subunit and its core fragment, but not the human chorionic gonadotropin. Results: The initial increases in nocturnal sleeptime total U-LH concentrations over the cutoff value of 0.7 IU/L occurred at around the same time (around 9–10 years of age) in both sexes, which could not be detected in waketime urine samples. The mean first age for the nocturnal sleeptime total U-LH concentrations to reach or surpass the cutoff was 10.7 years (range: 10.2–11.6 years) in boys and 11.8 years (range: 10.7–13.4 years) in girls, showing no statistically significant difference between the sexes (p =.15). The mean time span from the age at which sleeptime total U-LH concentration first exceeded the 0.7 IU/L level to observing pubertal stage 2 was 1.5 years in boys and 0.1 years in girls. Conclusions: Findings in our population with a limited sample size suggest that the timing of central pubertal activation is a sex-independent phenomenon, which can be observed by monitoring the nocturnal sleeptime total LH concentrations in urine. The lag time from central pubertal activation of gonadotropin secretion to the clinical onset of puberty is significantly longer in boys.

AB - Objective: We designed a longitudinal study to investigate the association between the ages of central pubertal activation and the appearance of clinical signs of puberty and determined total luteinizing hormone (LH) immunoreactivity in daytime- and nocturnal sleeptime-excreted urine samples. Patients and Measurements: Thirty healthy volunteers (17 boys and 13 girls, aged 3.4–15.2 years and 4.3–14.3 years, respectively, at the beginning of the study) were included. Male and female subjects were followed for an average of 15 visits during 5.5 and 5.8 years on average, respectively. At each visit, subjects provided 24-h urine samples divided into nocturnal sleeptime and waketime portions according to the participant's sleep-and-wake rhythm. Total urinary LH (U-LH) concentrations were measured in duplicate by Delfia® IFMA (Wallac), which has been designed specifically to detect intact LH as well as the beta subunit and its core fragment, but not the human chorionic gonadotropin. Results: The initial increases in nocturnal sleeptime total U-LH concentrations over the cutoff value of 0.7 IU/L occurred at around the same time (around 9–10 years of age) in both sexes, which could not be detected in waketime urine samples. The mean first age for the nocturnal sleeptime total U-LH concentrations to reach or surpass the cutoff was 10.7 years (range: 10.2–11.6 years) in boys and 11.8 years (range: 10.7–13.4 years) in girls, showing no statistically significant difference between the sexes (p =.15). The mean time span from the age at which sleeptime total U-LH concentration first exceeded the 0.7 IU/L level to observing pubertal stage 2 was 1.5 years in boys and 0.1 years in girls. Conclusions: Findings in our population with a limited sample size suggest that the timing of central pubertal activation is a sex-independent phenomenon, which can be observed by monitoring the nocturnal sleeptime total LH concentrations in urine. The lag time from central pubertal activation of gonadotropin secretion to the clinical onset of puberty is significantly longer in boys.

KW - central puberty

KW - first morning voided

KW - hypothalamic–pituitary–gonadal axis

KW - luteinizing hormone

KW - onset of puberty

KW - sleeptime

KW - urinary

U2 - 10.1111/cen.14974

DO - 10.1111/cen.14974

M3 - Journal article

C2 - 37772429

AN - SCOPUS:85173941096

VL - 99

SP - 552

EP - 558

JO - Clinical Endocrinology

JF - Clinical Endocrinology

SN - 0300-0664

IS - 6

ER -