Girls with idiopathic central precocious puberty did not display substatial changes in body mass index after treatment with gonadotropin-releasing hormone analogues.

AIM: To evaluate changes in body mass index (BMI) in girls during and after treatment for idiopathic central precocious puberty (iCPP). METHODS: We studied 123 girls receiving gonadotropin-releasing hormone analogue (GnRHa)treatment for iCPP from 2009 to 2019. Pubertal and anthropometric measurements were monitored at routine clinical visits. BMI standard deviation scores (SDS) were estimated at baseline and followed in two stages from baseline to end of treatment (median 18.9 months) and from end of treatment to end of follow-up (median 18.2 months). The influence of baseline BMI SDS and the frequency and dose of treatment was evaluated using BMI trajectories and latent class mixed models. RESULTS: The median age at treatment initiation was 8.5 years. The median BMI SDS at baseline was 0.7, corresponding to a median BMI of 17.4 kg/m2. Overall, no changes in BMI SDS were observed during treatment. According to baseline BMI subgroups, an increasing trend in BMI trajectories during treatment was observed for girls in the lowest BMI group. After treatment, most girls maintained stable BMI levels. CONCLUSION: Our retrospective study did not provide evidence that GnRHa treatment for iCPP had a significant impact on BMI trajectories in girls.

Minipuberty of human infancy - A window of opportunity to evaluate hypogonadism and differences of sex development?

Activation of the hypothalamic-pituitary-gonadal (HPG) axis happens in 3 phases during life. The first phase is during fetal life and is only separated from the second phase, called minipuberty, by the high concentration of placental hormones at birth. The third period of activation of the HPG axis is puberty and is well-described. Minipuberty consists of the neonatal activation of the HPG axis, mainly in the first 1-6 months, where the resulting high levels of gonadotropins and sex steroids induce the maturation of sexual organs in both sexes. With gonadal activation, testosterone levels rise in boys with peak levels after 1-3 months, which results in penile and testicular growth. In girls, gonadal activation leads to follicular maturation and a fluctuating increase in estrogen levels, with more controversy regarding the actual influence on the target tissue. The regulation of the HPG axis is complex, involving many biological and environmental factors. Only a few of these have known effects. Many details of this complex interaction of factors remain to be elucidated in order to understand the mechanisms underlying the first postnatal activation of the HPG axis as well as mechanisms shutting down the HPG axis, resulting in the hormonal quiescence observed between minipuberty and puberty. Minipuberty allows for the maturation of sexual organs and forms a platform for future fertility, but the long-term significance is still not absolutely clear. However, it provides a window of opportunity in the early detection of differences of sexual development, offering the possibility of initiating early medical treatment in some cases.