ESPE Abstracts

Background: The onset of physiological puberty in females is characterized by physical, hormonal, and genital changes. However, a single specific parameter to early identify these modifications does not exist; its identification could be extremely useful in the evaluation of pubertal development disorders. The uterine artery pulsatility index (PI), defined as systolic peak – diastolic peak/average speed of maximum flow, is an expression of vascular compliance in the uterine artery. Circulating estrogen reduce vascular resistance and, consequently, the PI values.

Objective and hypotheses: The end-point was to assess the accuracy of the uterine artery PI in the evaluation of the pubertal status and to set a cut-off value to classify prepubertal vs pubertal girls.

Method: 495 girls (mean age 8.6±2.17 years) referring to our hospital from September 2005 to March 2013 for the evaluation of pubertal disorders were enrolled. Exclusion criteria were GnRH-indipendent puberty, Turner syndrome, Prader–Willi syndrome, and patients under GnRH-analogs treatment. Tanner score, LH peak measurement after GnRH stimulation, ultrasound uterine and ovarian diameters, and PI values were assessed. ANOVA and ROC analysis were performed.

Results: PI values in the prepubertal (n=207), pubertal (n=117), and the CPP (n=171) groups were respectively: 6.3±1.42, 3.4±1.10, and 3.9±1.48 (P<0.0001). The best PI cut-off value to distinguish pubertal from prepubertal girls was 4.6 (sensibility 83%, specificity 94%, PPV 95%, NPV 80%, and accuracy 87%). ROC area for LH peak and for combined PI-longitudinal uterine diameter were 0.9439 and 0.9272% (P=0.7931) respectively.

Conclusion: The ultrasound uterine artery PI can be considered an accurate and non-invasive parameter for the diagnosis of pubertal activation.