anti-sperm antibodyAny of a group of antibodies produced against four distinct components of the sperm. While ASAs are linked to infertility, their presence is not associated with a particular disease; ASAs may be found in the circulation, either free or as immune complexes, in seminal fluid and/or attached to the sperm surface.
IgA, IgG, IgM < 15% binding.
Low titres (< 1:8 of ASAs) are present in 90% of prepubertal boys and are of no significance; up to 50% of infertile women have anti-sperm antibody titres of ≥ 1:16, most commonly as IgG or IgA anti-sperm (tail-immobilising) antibodies, while male homosexuals tend to develop IgM anti-sperm (head-agglutinating) antibodies.
Serum, semen IgE.