ABSTRACT
<p><b>OBJECTIVE</b>To study the effect of tea saponin in ameliorating nonoxynol(N-9) spermicidal action in vitro.</p><p><b>METHODS</b>According to the improved spermicidal test method in vitro recommended by International Planned Parenthood Foundation (IPPF), we evaluated the minimum spermicidal concentration of N-9, tea saponin and their mixed solution in 20 s and 3 min.</p><p><b>RESULTS</b>The minimum spermicidal concentration of N-9 in the mixed solution was (0.13 +/- 0.05) g/L in 20 s and (0.05 +/- 0.004) g/L in 3 min, and that of the tea saponin in the mixed solution was (2.40 +/- 1.07) g/L in 20 s and (1.27 +/- 0.38) g/L in 3 min, compared with the single ingredient N-9 [(0.48 +/- 0.15) g/L in 20 s, (0.34 +/- 0.079 g/L in 3 min], and tea saponin [(5.78 +/- 1.40) g/L in 20 s, (1.71 +/- 0.176) g/L in 3 min], P < 0.01.</p><p><b>CONCLUSION</b>Tea saponin can improve N-9 spermicidal action in vitro, and tea saponin and nonoxynol have proved of synergic effect.</p>