GnRH Stimulation Test in Precocious Puberty: Single Sample is Adequate for Diagnosis and Dose Adjustment

Objective: Gonadotropin stimulation test is the gold standard to document precocious puberty. However, the test is costly, time-consuming and uncomfortable. The aim of this study was to simplify the intravenous gonadotropin-releasing hormone (GnRH) stimulation test in the diagnosis of precocious puberty and in the assessment of pubertal suppression. Methods: Data pertaining to 584 GnRH stimulation tests (314 testsfor diagnosis and 270 for assessment of pubertal suppression) were analyzed. Results: Forty-minute post-injection samples had the greatest frequency of “peaking luteinizing hormone (LH)” (p<0.001) in the diagnostic tests when the cut-off value was taken as 5 IU/L for LH, 40th minute sample was found to have 98% sensitivity and 100% specificity in the diagnosis of precocious puberty, while the sensitivity and specificity of the 20th minute sample was 100% in the assessment of pubertal suppression. Conclusion: LH level at the 40th minute post-injection in the diagnosis of central precocious puberty and at the 20th minute post-injection in the assessment of pubertal suppression is highly sensitive and specific. A single sample at these time points can be used in the diagnosis of early puberty and in the assessment of pubertal suppression. Conflict of interest:None declared.