Interrelationships between sex hormone-binding globulin and 17 beta-estradiol, testosterone, 5 alpha-dihydrotestosterone, thyroxine, and triiodothyronine in prepubertal and pubertal girls.

Sex hormone-binding globulin (SHBG), 17 beta-estradiol (E2), testosterone (T), 5 alpha-dihydrotestosterone (DHT), T4, and T3 were measured in prepubertal (age, 1--8 yr; n = 44; group I) and pubertal (age, 9--16 yr; n= 56; group II) girls. The main results were as follows. 1) In group I, a higher mean (+/- SEM) value for SHBG was found (73.5 +/- 2.82 nmol/1) compared to that in Group II (56.8 +/- 3.37; P less than 0.001). 2) Despite a significant increase of the androgens T and DHT with age in group I (rT.age = 0.578; rDHT.age = 0.544; P less than 0.01 for each), no significant alteration of SHBG with age was present. 3) In group II, a significant decrease of SHBG with age occurred (rSHBG.age = -0.438; P less than 0.35) along with the expected increases of E2 (rE2.age = 0.691; P less than 0.001), T (rT.age = 0.765; P less than 0.001), and DHT (rDHT.age = 0.712; P less than 0.001). 4) The analysis of the data by partial correlation coefficients supports the suggested role for androgens in the decline of SHBG during puberty in girls, whereas correlations of SHBG with E2 or the thyroid hormones were insignificant.