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

2013-08-27T00:00:00Z (GMT) by Albin A.-K. Norjavaara E.
<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), EC<sub>50</sub>. The corresponding EC<sub>50</sub> 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.