“…When progesterone or testosterone was added to a series of sera, sperm-agglutinating activity was induced in some sera (previously negative) and increased in others presenting spermagglutinating activity before the addition of steroids (Boettcher & Kay, 1973; Boettcher, 1974 b). It may be of importance, however, that the steroids were added in high (non-physiological) concentrations and that the sperm-agglutinating activity was quantified not by titration, but by counting the number of agglutinates, which does not appear to be a reliable approach for quantitation of sperm-agglutinating activity (Mettler & Gradl, 1975). Ingerslev (1979), in contrast to Boettcher and coworkers found no significant titre-decrease by the tray agglutination technique after extensive dialysis and ultrafiltration, and addition of progesterone in the concentrations described by Boettcher (1974 b) did not induce sperm-agglutinating activity in any of thirty female sera, negative by the tray agglutination technique.…”