Endocrine Abstracts

JOINT1479

Objective: We aimed to identify the contributing physical predictors for menarche and further to establish critical weight for menarche onset in Chinese girls.

Methods: This was a retrospective study. The sample was composed of 253 girls who visit within 3 months after menarche. For propensity score matching, data of 253 girls with similar chronological age and mid-parental height who haven’t menarche yet were collected. All girls were from Beijing city, China and visit pediatric clinic during 2018 to 2023. Receiver operator characteristic curve was performed to determine cutoff values. Multivariate logistic regression was used to construct a nomogram. The discriminatory ability of the model was determined by calculating the area under the curve (AUC). Moreover, calibration analysis and decision curve analysis (DCA) of the model were performed.

Results: The average age of menarche of the 253 girls was 10.2±1.0 years, with average weight of 42.9±6.8kg, height of 148±5.1cm and BMI of 20.2±2.5kg/m², with significant higher compared to pre-menarche girls with similar age and mid-parental height (P <0.01). Among the girls of different menarche age groups, height, weight, BMI, and their standard deviation scores were compared, there was significant difference between groups except weight (P = 0.088). Based on receiver operating characteristic (ROC) curve analysis, weight of 36.6kg was significantly related to menarche occuring, and the specificity and sensitivity were 65.2% and 81.7%, respectively. A nomogram was built based on weight, the proportion of height to mid-parental height, and bone age. The predictive model yielded an AUC of 0.818 (95% CI, 0.780, 0.856). The predictive model was well-calibrated, and DCA showed when the threshold probability of menarche below 80%, using the proposed nomogram to predict menarche would obtain more benefit than using weight prediction alone.

Conclusions: Menarche age is highly related to physical development. The optimal critical value of weight has important application value in menarche. Besides, a nomogram was constructed for predicting menarche by physical status. Physical growth, as a simple and easily obtainable information, can be reliable indicators for predicting menarche.