The Anti-Sperm Antibody test detects antibodies that are directed against sperm cells, which can interfere with fertility. These antibodies can affect sperm motility, function, and the ability to fertilize an egg. Elevated levels of anti-sperm antibodies can lead to male infertility or female infertility in cases where the antibodies impact sperm reaching and fertilizing the egg. This test is often used in fertility evaluations for both men and women. A blood or semen sample may be required for this test, depending on the clinical context.