Supplementary Material for: Pubertal Growth and Serum Testosterone and Estradiol Levels in Boys

<b><i>Background/Aims:</i></b> To study serum testosterone and estradiol in healthy boys in relation to growth during puberty up to peak height velocity (PHV). <b><i>Methods:</i></b> Growth velocity was analyzed through testosterone (n = 41) and 17β-estradiol (n = 37) 24-hour profiles in a dose-response model. Participants were 26 healthy boys admitted for short or tall stature or participating as healthy volunteers at the Queen Silvia Children's Hospital. Other inclusion criteria included the following: gestational age 37-42 weeks, birth weight and length >-2 standard deviation score (SDS) and prepubertal height and weight within ±3 SDS. Testosterone was measured using a modified radioimmunoassay (RIA) with a detection limit of 0.03 nmol/l. Estradiol was determined using an ultrasensitive extraction RIA with a detection limit 4 pmol/l. A sixth-grade polynomial was fitted to each child's growth data, giving growth velocity and age at PHV. <b><i>Results:</i></b> Growth velocity increased by 50% from prepubertal growth to PHV at a morning testosterone level of 3.1 nmol/l (95% confidence interval 2.4-4.2), EC₅₀. The corresponding EC₅₀ of 17β-estradiol was 6.5 pmol/l (3.2-13). Boys approaching PHV (<4% remaining) had morning testosterone levels >10 nmol/l and 17β-estradiol >9 pmol/l. <b><i>Conclusion:</i></b> Observed early puberty/initial mid puberty morning testosterone levels of 2.4-4.2 nmol/l are associated with a 50% increase in growth velocity from prepubertal growth to PHV in healthy boys

Supplementary Material for: Estradiol and Pubertal Growth in Girls

<b><i>Aim:</i></b> The objective of this study was to determine estradiol levels and assess their relationship to pubertal growth in girls. <b><i>Methods:</i></b> Thirty-seven 24-hour profiles of serum 17β-estradiol were retrospectively analyzed in relation to growth in 27 healthy girls admitted for short/tall stature (n = 20) or recruited as healthy volunteers at Göteborg Pediatric Growth Research Center (GP-GRC). <b><i>Inclusion Criteria:</i></b> Birth weight and length above –2 SDS, gestational age 37–42 weeks, prepubertal height and weight within ±3 SDS and normal growth hormone secretion. Serum estradiol was determined by a validated ultrasensitive extraction radioimmunoassay (detection limit 4 pmol/l). A sixth-grade polynomial was fitted to each girl’s growth data. Growth velocity and age at peak height velocity (PHV) was calculated. <b><i>Results:</i></b> A dose-response model was used to find the morning 17β-estradiol level at which half of the maximal pubertal growth up to PHV had occurred, EC₅₀, which was 20 pmol/l with a 95% confidence interval of 13–31. When 17β-estradiol exceeds early pubertal levels (Tanner breast stage 2, 10–51 pmol/l), less than 25% of the potential pubertal growth velocity up to PHV remains. <b><i>Conclusions:</i></b> Morning 17β-estradiol in the low early pubertal range (13–31 pmol/l) is associated with increasing growth velocity