Salivary testosterone: relationship to unbound plasma testosterone in normal and hyperandrogenic women

A sensitive radioimmunoassay (RIA) was used to measure salivary testosterone levels in normal women, in patients with polycystic ovaries (PCO), and in women with hirsutism. There was a highly significant correlation (r = 0.79, P less than 0.001) between the concentration of testosterone in saliva [12.3 +/- 7.8 (SD) pg/ml] and the concentration of unbound testosterone in plasma (5.2 +/- 3.1 pg/ml) in matched samples collected from 56 women including normals, patients with clinical signs of hyperandrogenism, and women treated with a combination of cyproterone acetate (CA) and ethinyl oestradiol (EE). The unbound plasma testosterone was measured in the dialysate directly using a sensitive RIA. Salivary and plasma testosterone levels in patients with PCO (20.6 +/- 8.5 and 626 +/- 187 pg/ml respectively, n = 14) and in those with hirsutism (13.9 +/- 5.6 and 421 +/- 170 pg/ml, n = 30) were significantly higher (P less than 0.001) than levels in normal women (7.7 +/- 2.6 and 196 +/- 68 pg/ml, n = 36). Treatment for 3 months with CA and EE resulted in a decrease (mean 68%) in salivary testosterone levels in all patients studied (n = 15), but the suppression of plasma testosterone (mean 34%) was not observed in all cases. It is concluded that measurement of salivary testosterone gives a useful indication of levels of biologically available androgen in hyperandrogenic women, before and during CA/EE therapy.