Updated reference values in pelvic ultrasonography for a Spanish population of healthy girls between 6 and 12 years old

Background Pelvic ultrasonography (PUS) of the uterus and ovaries allows the diagnosis of changes in sexual development. However, the reference values used in Spain originate from old studies conducted in other countries. Objective To determine reference uterine and ovarian measurements by PUS and according to pubertal status and bone age in a Spanish population of healthy girls aged between 6 and 12 years. Materials and methods Descriptive cross‐sectional study performed on 221 healthy girls from 2017 to 2019. Ovarian and uterine measurements were described and associated with chronological age, bone age, and Tanner stage. ROC curves were used to assess the predictive value of tests for Tanner stage II. Results We described reference values for all PUS uterine and ovarian measurements assessed. Subjects in Tanner II (thelarche) had a mean age of 9.7 years (SD = 1.1) and mean BMI of 19.2 kg/m2. Fundal–cervical ratio changed from 1:1 to 2:1 at 12 years of chronological age (62.5% with 1:1 ratio; p
The study provides updated pelvic ultrasound reference values for uterine and ovarian measurements. According to our findings, a significant change in uterine length (p = 0.0020), ovarian transverse diameter (p