Abstract
<title>Abstract</title> <p>Background Human chorionic gonadotropin (hCG) serves not only as a diagnostic stimulation test for evaluating testicular function but also as a key therapeutic modality for hypogonadotropic hypogonadism (HH). However, there are significant individual differences in hCG response among pediatric patients, and currently, there is a lack of effective clinical indicators to predict hCG response. The purpose of this study is to explore factors impacting hCG response in children with micropenis who are prepubertal. Methods This study enrolled prepubertal boys with micropenis and divided them into a low-response group and a normal-response group to compare clinical data between the two groups. Utilized multivariate logistic regression, correlation analysis, and receiver operating characteristic (ROC) curves to identify predictors of hCG response. Results A total of 92 prepubertal boys with micropenis were enrolled, including 20 with low hCG response and 72 with normal response. In comparison to the normal - response group,the low-response group demonstrated lower levels of peak luteinizing hormone ( LH ), a decreased ratio of peak LH to peak follicle - stimulating hormone ( FSH ) levels ( peak LH/FSH ), as well as reduced increases in testosterone ( ΔTT ), penile length ( ΔPL ), and relative change in penile length ( ΔPL/PL ) (P < 0.05). Multivariate logistic regression analysis indicated that peak LH/FSH (OR = 0.059, 95% CI: 0.003–0.579, P = 0.028) independently predicted a low hCG response. The peak LH/FSH was correlated positively with TT, ΔTT, ΔPL, and ΔPL/PL after hCG stimulation (P < 0.05). ROC curve analysis revealed that the area under the curve (AUC) for predicting low hCG response based on peak LH/FSH levels was 0.724 (95% CI: 0.595–0.854, P = 0.002), corresponding to an optimal cutoff value of 0.562, a sensitivity of 95.0%, and a specificity of 43.1%. Conclusion The peak LH/FSH ratio may serve as a potential predictive indicator of low hCG response in prepubertal children with micropenis. A lower peak LH/FSH ratio aids in identifying patients with micropenis who exhibit a low hCG response and guides subsequent treatment strategies.</p>