It has become increasingly evident within the last few decades that immunologic factors are involved in some aspects of the reproductive process and hence in the physiology and pathology of the genital tract. The concept that immune phenomena participate in human reproduction is not new. There are examples throughout the history of man that immune phenomena may have influenced the reproductive process. For example, the Bible states that Sarah was sterile for a long time but conceived in the later years of her marriage. This could be interpreted to mean that continued exposure to her husband's ejaculated antigens reΒ sulted in antibody response, sufficient to induce sterility. However, after continence of long duration, the antibody level declined and conception became possible. Another of speculation is Darwin's Descent of Man, which contains a number of stateΒ source ments to the effect that profligacy of women may account for their "small fertility". The inference is that repeated exposure to antigenic material in the ejaculate causes antibody responses that lead to infertility (KATSH and KATSH, 1965). This is directly related to the modern postulate that prostitutes do not conceive because of antisperm antibodies acquired by frequent contact with semen.