目的: 评估乳房发育女童晨尿促黄体生成素(luteinizing hormone，LH)水平，以确定晨尿LH对于评价中枢性性早熟(central precocious puberty，CPP)的价值。方法: 收集2018年9月至2021年4月期间因性早熟就诊于北京大学第三医院儿科门诊并住院行促性腺激素释放激素(gonadotropin-releasing hormone，GnRH)激发试验的女童共108例，根据CPP诊断标准分为CPP组(n=45)和非CPP组(n=63)，比较两组的临床特征及激素水平，采用受试者工作特征(receiver operating characteristic，ROC)曲线分析得出尿LH的临床参考切割值。对尿LH水平与临床常用指标进行相关性分析，进一步评估尿LH在CPP诊断中的价值。结果: ROC曲线分析显示，晨尿LH水平对CPP诊断有意义，切割值为0.69 IU/L时，其敏感度为85%，特异度56.9%，曲线下面积为0.804(P < 0.001)。对GnRH激发试验前的基本临床特征进行二元Logistic回归分析，提示晨尿LH水平、子宫体积、卵巢体积、T骨龄提前程度对于诊断女童CPP均有预测意义(OR值分别为2.125、1.961、1.564、2.672)，建立预测模型，ROC曲线下面积为0.904(P＜0.001)。进一步行相关性分析，晨尿LH水平与GnRH激发试验前血激素水平(LH、FSH、雌激素)、GnRH激发试验后血LH峰值、T骨龄、子宫体积均呈正相关，r值分别为0.462、0.373、0.242、0.360、0.373和0.263，P值分别为 < 0.001、 < 0.001、0.013、 < 0.001、 < 0.001和0.007。结论: 晨尿LH水平对CPP的诊断有较好的提示意义，同时结合T骨龄提前程度及盆腔超声测量可进一步提高其对女童CPP诊断的预测价值。

Objective: To evaluate the level of first morning voided (FMV) urinary luteinizing hormone (LH) in girls with breast development, and to determine the value of FMV urine LH in the evaluation of central precocious puberty (CPP). Methods: From September 2018 to April 2021, among the patients who were admitted to the Department of Pediatrics of Peking University Third Hospital for "precocious puberty" and underwent gonadotropin-releasing hormone (GnRH) stimulation test, a total of 108 girls were enrolled. According to CPP diagnostic criteria, they were divided into CPP group (n=45) and non-CPP group (n=63). The clinical characteristics and hormone levels of the two groups were compared. Receiver operating characteristic (ROC) curve was used to analyze the cut-off value of FMV urinary LH in the diagnosis of CPP in girls. Further analyses were done to evaluate the value of FMV urinary LH in the diagnosis of CPP using correlation analysis between urinary LH level and common clinical cha-racteristics. Results: ROC curve analysis showed that FMV urine LH level was significant for the diagnosis of CPP. The cut-off value of FMV urine LH was 0.69 IU/L (specificity 56.9%, sensitivity 85.0%, area under curve 0.804, P < 0.001). The basic clinical characteristics without GnRH stimulation test were analyzed by binary Logistic regression analysis, indicating that the level of FMV urine LH, uterine volume, ovarian volume and advanced T-bone age had predictive significance for CPP diagnosis in girls (OR values were 2.125, 1.961, 1.564 and 2.672, respectively). The prediction model was established and the area under the ROC curve was 0.904, P < 0.001. The level of FMV urine LH was positively correlated with the levels of serum LH, FSH and estrogen before GnRH stimulation test, the peak value of blood LH after GnRH stimulation test, T bone age and uterine volume, with r values of 0.462, 0.373, 0.242, 0.360, 0.373 and 0.263, respectively, and P values were < 0.001, < 0.001, 0.013, < 0.001, < 0.001 and 0.007, respectively. Conclusion: FMV urine LH can provide a good indication for the diagnosis of CPP. Combining with bone age advanced level and pelvic ultrasound measurement, the predictive value of FMV urine LH can be further improved for the diagnosis of CPP in girls.