Towards an individualized management of pubertal induction in girls with hypogonadism: insight into the best replacement outcomes from a large multicentre registry.

OBJECTIVE: An evidence-based pubertal induction scheme in hypogonadal girls is still to be established. Interestingly, literature data report a suboptimal uterine longitudinal diameter (ULD) in >50% of treated hypogonadal women, negatively influencing their pregnancy outcomes. This study aims to investigate auxological and uterine outcomes of pubertal induction in girls in the light of underlying diagnosis and therapeutic schemes used. DESIGN: Retrospective analysis of longitudinal data from a multicentric registry. METHODS: Auxological, biochemical, and radiological data were collected at baseline and during follow-up in 95 hypogonadal girls (chronological age > 10.9 years, Tanner stage ≤ 2) treated with transdermal 17ß-oestradiol patches for at least 1 year. Induction was started at a median dose of 0.14 mcg/kg/day with a 6-monthly increase and was considered completed for 49/95 patients who started progesterone with a concomitant oestrogen adult dose. RESULTS: At the end of induction, the achievement of the complete breast maturation was associated with a 17ß-oestradiol dose at progesterone introduction. ULD showed a significant correlation with a 17ß-oestradiol dosage. Final ULD was >65 mm in only 17/45 girls. At multiple regression analysis, pelvic irradiation represented the major determinant of reduced final ULD. After correction for uterine irradiation, ULD was associated with the 17ß-oestradiol dose at progesterone introduction. Final ULD was not significantly different from the one assessed after progesterone introduction. CONCLUSIONS: Our results provide evidence that progestins, hampering further changes in uterine volume and breast development, should be introduced only in the presence of a concomitant adequate 17ß-oestradiol dose and an appropriate clinical response.