Sperm Antibody, Indirect, Serum
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Sperm antibodies are associated with some cases of infertility. For fertilization to occur, the sperm head must first attach to the zona pellucida of the egg. Sperm antibodies interfere with this binding. While there is consensus that these antibodies play a role in infertility, the percentage of sperm that must be bound by antibodies before fertility is adversely affected is less clear. In 1 of the more extensive investigations to date, Bronson, et al (1) reported that of couples exhibiting abnormal postcoital tests, 24% of sera from men and 35% of sera from women exhibited sperm antibodies. When sperm were exposed to serum containing head-directed antibodies, "...a nearly complete inhibition of sperm attachment to zona pellucida..." was observed.
Semen and serum may contain sperm antibodies.
-Semen is the preferred specimen type for males.
-Serum is the preferred specimen type in females.
-As an alternate specimen type (semen is preferred) when semen cannot be obtained
-As follow-up test when sperm agglutination is noted in the ejaculate
-With a history of testicular trauma, biopsy, vasectomy reversal, genital tract infection, or obstructive lesions of the male ductal system
-Preferred test for sperm antibodies
-With an abnormal postcoital test
-With unexplained infertility
-With history of genital tract infection or receptive anal or oral intercourse
Positives are reported as percentage of sperm with:
-Class of antibody involved (IgG and IgA)
-Site of binding (head, midpiece, tail, and/or tail tip)
Normal specimens display <50% total binding.
Greater than 50% binding is usually required to significantly lower a patient's fertility.
The significance of percent binding inversely related to patient sperm count.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Sperm antibody testing is not recommended for routine infertility testing.
Preferred testing fluid for males suspected of sperm antibodies is semen. In cases where specimen production may present difficulties, a serum specimen can be tested.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Bronson R, Cooper G, Rosenfeld D: Sperm antibodies: their role in infertility. Fertil Steril 1984;42:171-183
2. Marshburn PB, Kutteh WH: The role of antisperm antibodies in infertility. Fertil Steril 1994;61:799-811