Sperm-agglutinating antibodies in infertile couples.

In a selected group of 150 infertile couples, sperm-agglutinating antibodies were examined by a microagglutination technique. Sperm-agglutinating activity was observed in sera from 12 men (8%) and 16 women (11%). Antibodies in seminal plasma were demonstrated in 8 men with correspondingly high serum titers. The type of agglutination in these cases was head to tail. Head-to-head agglutination was found in only 3 men, who all had agglutinating activity in serum only. An abnormal postcoital test was found in 57% of the couples, and 13% of the men and 14% of the women in these couples had agglutinating antibodies. A negative postcoital test was related more often to high than to low titer in female sera.