Twenty sera from fertile and infertile women were examined for antibodies to spermatozoa or to seminal plasma, to determine which of the five techniques tested provided reliable evidence of allergic infertility.
Ten sera agglutinated seminal plasma coated tanned red cells, six agglutinated spermatozoa, ten gave mixed cell antiglobulin agglutination and fourteen gave immunofluorescent reactions for IgG or igM antispermatozoal antibodies, and three were cytotoxic to sperm.
The results of tests for seminal plasma agglutinins were unrelated to those of any of the other tests, and it is believed that factors other than antibody also clump these antigen-coated cells. There was good agreement in the results obtained by direct sperm agglutination, mixed cell antiglobulin agglutination and strong immunofluorescent staining of the sperm head. The antiglobulin and immunofluorescent techniques also detect nonagglutinating (‘incomplete’ or ‘univalent’) antibody.
One of the three sera cytotoxic to sperm had no antibody detected by the other tests. The sperm may have been killed by an inflammatory substance or a systemically absorbed contraceptive. This case illustrates the necessity of combining tests for cytoxicity with at least one technique for antispermatozoal antibody in order to detect allergic infertility.