A single sample GnRHa stimulation test in the diagnosis of precocious puberty

To determine the appropriate sampling time for LH post leuprolide challenge.A retrospective analysis of multi-sample GnRHa stimulation tests performed in 155 children (aged 1–9？years) referred for precocious puberty to Texas Children’s Hospital.After 20 mcg/kg of SQ leuprolide acetate, samples were obtained at 0, 1, 3, and 6 hours.Of 71 children with clinical evidence of central precocious puberty, fifty nine children had a peak LH >5 mIU/mL. 52 (88%) of these responders had positive responses at 1 hour (95% CI is 80–96%), whereas all 59 children (100%) had a peak LH response >5 mIU/mL at 3 hours (95% CI is 94-100%), P？=？0.005.A single serum LH sample collected 3 hours post GnRHa challenge is the optimal sample to establish the diagnosis of central precocious puberty.