Spontaneous spermagglutination in ejaculates from men with head-to-head or tail-to-tail spermagglutinating antibodies in serum.

Weak or sometimes up to moderate spermagglutination was encountered in ejaculates from a group of men without spermagglutinating antibodies in serum. A similar pattern of spermagglutination was seen in ejaculates from men with head-to head (H-H) spermagglutinating antibodies in serum, even when a high titer (greater than or equal to 1:64) of antibodies was present. In contrast, men with high titers of tail-to-tail (T-T) sperm agglutinating antibodies in serum showed very marked or complete spermagglutination in the ejaculates. The agglutination in ejaculates from men with low titers (less than or equal to 1:32) of T-T spermagglutinating antibodies in serum was much less conspicuous and equaled that in ejaculates from men without such antibodies. This indicates that only a high titer of T-T spermagglutinating antibodies is associated with marked or complete spermagglutination in ejaculates.