Testicular ultrasound to stratify hormone references in a cross-sectional norwegian study of male puberty

Abstract

Context: Testicular growth represents the best clinical variable to evaluate male puberty, butcurrent pediatric hormone references are based on chronological age and subjective assessmentsof discrete puberty development stages. Determination of testicular volume (TV) by ultrasoundprovides a novel approach to assess puberty progression and stratify hormone reference intervals.Objective: The objective of this article is to establish references for serum testosterone and keyhormones of the male pituitary-gonadal signaling pathway in relation to TV determined byultrasound.Design, Setting, and Participants: Blood samples from 414 healthy Norwegian boys betweenages 6 and 16 years were included from the cross-sectional "Bergen Growth Study 2."Participants underwent testicular ultrasound and clinical assessments, and serum samples wereanalyzed by liquid chromatography tandem-mass spectrometry and immunoassays.Main Outcome Measures: We present references for circulating levels of total testosterone,luteinizing hormone, follicle-stimulating hormone, and sex hormone-binding globulin inrelation to TV, chronological age, and Tanner pubic hair stages.Results: In pubertal boys, TV accounted for more variance in serum testosterone levels thanchronological age (Spearman r = 0.753, P