Monitoring strategy and efficacy of GnRH analogue therapy in girls with central precocious puberty and early puberty

Abstract

Objectives: This study evaluated the effectiveness of gonadotropin-releasing hormone analogue (GnRHa) therapy in girls with central precocious puberty (CPP) and early puberty (EP), aiming to identify a reliable marker for treatment monitoring and assessing long-term outcomes.

Study design: A retrospective case study between 2001 and 2024, a total of 265 girls with rapidly progressive CPP or EP who received GnRHa therapy were enrolled. A GnRH stimulation test was performed after 12 weeks of therapy. Receiver operating characteristic curves and the Youden index were used to identify an optimal marker and define the cut-off value indicating effective suppression. Among them, 186 reached adult height, and their height outcomes were analyzed to identify predictive factors.

Results: After 12 weeks of GnRHa therapy, effective suppression was achieved in 94.3 % of patients. Unstimulated LH was a strong predictor (AUC = 0.85), with a cut-off of <0.4 IU/L (sensitivity, 65.5 %; specificity, 86.7 %). Growth outcomes showed that patients with CPP had better adult height than those with EP (156.5 vs. 153.9 cm, p < 0.001). Positive predictors included second-year growth velocity, predicted adult height at treatment initiation, and bone age standard deviation score, while a unstimulated LH level was negatively associated with final height. Long-term follow-up revealed that 34.9 % of patients had abnormal bone mineral density (31.5 % osteopenia and 3.4 % osteoporosis), although obesity rates were comparable to the general population.

Conclusions: This study highlights the importance of early intervention and effective monitoring strategies, with unstimulated LH emerging as a useful marker for treatment efficacy.

Keywords: Bone mineral density; Central precocious puberty; Early puberty; GnRH analogue; GnRH test.