ESPE Yearbook of Paediatric Endocrinology

Clin Endocrinol (Oxf). 2025 May;102(5):578-588. doi: 10.1111/cen.15208. PMID: 39934096.

Brief summary: This study assessed the clinical reliability of first-morning urinary LH (U-LH) levels to determine pubertal onset. Despite moderate day-to-day variation, a single U-LH measurement was sufficient to classify children as prepubertal, peripubertal, or pubertal.

First-morning urinary gonadotropin measurement offers a non-invasive alternative to serum sampling and GnRH stimulation test for assessing pubertal status. In this semi-longitudinal study of 354 healthy children, U-LH levels were classified as prepubertal (< 0.60 IU/l), highly likely pubertal (0.60–0.99 IU/l), and pubertal (≥ 1.00 IU/l). Demir et al. demonstrated that a single U-LH measurement, despite moderate day-to-day variation (~33% coefficient of variation), was sufficient to determine pubertal stage in over 95% of cases, with only 3.6% of boys and 4.9% of girls showing inconsistent classification across three consecutive mornings.

The first increase in mean U-LH concentrations occurred shortly after the age of 10 in both sexes, suggesting that U-LH captures early hypothalamic-pituitary-gonadal axis activation before obvious clinical progression. The findings reinforce earlier data showing that the rise in central gonadotropin secretion often precedes visible pubertal signs, and that the timing of central puberty onset is sex-independent (1).

The findings described in this article are aligned with a study demonstrating that both basal serum LH and single random urinary gonadotropin measurements can aid in the diagnosis of central precocious puberty (2). Although assay standardization and sample handling practices still require refinement, U-LH testing is emerging as a practical, low-burden diagnostic tool. It may serve as a first-line screening method, particularly in outpatient settings where stimulation testing is not feasible.

References: 1. Demir A, Hero M, Juul A, Main KM. Sex-independent timing of the onset of central puberty revealed by nocturnal luteinizing hormone concentrations. Clin Endocrinol (Oxf). 2023;99(6):552–558.2. Lee SY, Kim JM, Kim YM, Lim HH. Single random measurement of urinary gonadotropin concentration for screening and monitoring girls with central precocious puberty. Ann Pediatr Endocrinol Metab. 2021;26(3):178–184.