The investigation of immunological infertility

Immune reactions to spermatozoa may interfere with fertility in both males and females. These mechanisms may operate in a small, but significant, proportion of infertile couples, particularly when the duration of infertility is greater than three years. Antibodies to sperm may appear both in the blood and in genital tract secretions and their presence should be sought in both sites. The most suitable screening test for circulating anti-sperm antibodies in either partner is a method based on the complement-dependent antibody immobilization of sperm. This test may also be applied to cervical mucus as a routine in females. In males the detection of sperm immobilizing antibodies in blood serves as a reasonable guide to the existence of antibodies in seminal plasma where their presence may be confirmed using a gelatin agglutination test. Further information about the presence of locally secreted antibodies either in cervical mucus or in semen may be gained by using the sperm-cervical mucus contact (SCMC) test in which cross-testing with donor mucus or sperm will identify the site of local antibody production. Results based on immunofluorescence and sperm microagglutination methods are unreliable and lacking in correlation with continuing infertility and the routine use of these tests is not recommended.