A Clinical Experience of Pubertal Induction in Female Patients With Congenital Hypogonadotropic Hypogonadism (CHH) From an Endo-ERN Referral Center

Abstract

Female congenital hypogonadotropic hypogonadism (CHH) is a rare condition, with a strong genetic background, characterized by absent or incomplete pubertal development, for which inductive treatment with sex-hormone is required. Although the available data, mostly coming from studies in patients with Turner syndrome, indicate transdermal estradiol (TDE) as the first-choice formulation, no internationally validated therapeutic schemes are currently available. Furthermore, data on CHH patients are certainly lacking and there is no standard of care for pubertal induction in this specific population. The aim of our work was the retrospective analysis of the data from a collection of case reports of pubertal induction in CHH patients referred to our Center. Six patients underwent induction with transdermal estradiol (TDE) at the starting dose of 0.1µg/kg/day (night-time for the first 4-6 months), increased every 4-6 months up to the adult dose, for a mean period of 2.86 ± 0.45 ys. Micronized progesterone (200 mcg) was introduced at reaching of 50µg dose or if breakthrough bleeding occurred. Treatment was monitored through clinical and anthropometric evaluations at each dose modification. The average age of induction was 17.25 ± 1.41 ys, with each bone age> 13 ys. Three out of six patients already had a Tanner B2 stage at diagnosis. The mean times of pubertal advancement were respectively 1.3 ± 0.46 ys for the achievement of B3, 2.13 ± 0.29 ys for the B4 and 2.35 ± 0.77 ys for menarche; all the patients reached an adult breast conformation (B5) in 2.81 ± 0.28 ys. These data are consistent with physiological pubertal progress. All of them achieved adequate uterine development (medium longitudinal diameter 72.2 ± 3.37mm), except one patient with suboptimal development (54mm). The final height (FH) was adequate in all patients, with SDS FH +1.6 (-0.43 - +3.38), in spite of an average growth of 4.11 cm (2.5-6) ​​during the induction period and a growth rate > 2cm/year only in 50% of patients. No side effects were reported, and individual compliance and satisfaction were quite high. This clinical experience suggests that the adopted regimen, consistent with current literature, guarantees excellent efficacy and safety. However, further studies are needed to identify the optimal treatment in adolescents with CHH, taking into account their higher age at the start of induction, the modest impact on growth and final stature, to focus on the specific clinical objectives in these patients