SERO-SALIVARY PROGESTERONE CORRELATION

OBJECTIVES: The use of saliva has many advantages and the concentratio n of some sex steroids in saliva generally reflect serum levels. Howev er, recently doubts have been cast on this relationship [1,2]. This st udy was undertaken to establish any correlation between serum and sali vary progesterone in quiescent and dynamic states. METHODS. Serum and salivary progesterone were measured in normally cycling (N = 23), preg nant (N = 10) and 5 postmenopausal women on hormone replacement therap y, using non-isotopic enzyme immunoassay on microtiter plates develope d in this unit. RESULTS: Salivary progesterone was found to be approxi mately 1% of serum progesterone in normally cycling and pregnant women . There was good positive correlation between serum and salivary proge sterone in normally cycling, pregnant and the postmenopausal women. Th e linear regression equation is y = 0.009x + 0.035: r = 0.987, P < 0.0 01; y = -0.011x -0.079:r = 0.958, P < 0.001; and y = 0.014x+ 1.18: r = 0.714, P < 0.001, respectively. The maximum concentration of progeste rone in postmenopausal women was achieved simultaneously in serum and saliva at 2 h post therapy thereby supporting the theory of rapid ultr afiltration of steroids from blood to saliva [3]. CONCLUSIONS: Salivar y progesterone measurement reflects serum concentration and provide an attractive alternative to serum measurement. It should become increas ingly popular in gynecological and endocrinological investigations esp ecially in longitudinal studies.