Immunological factors and post coital test in unexplained infertility

24 couples facing longstanding primary or secondary infertility underwent semen analysis, PCT, functional evaluation of menstrual cycle, hysterosalpingography and laparoscopy. All clinical findings were normal with the exception of PCT which was positive in 13 and negative in 11. All the women underwent a multiple approach investigation of local and circulating antibodies production as well as cell mediated immunity against live spermatozoa. Sperm Immobilization Test (SIT) and Spermatotoxicity Tests (STT) were performed in a single experimental design on cervical mucus and blood serum. Leukocyte Migration Inhibition Test in presence of sperms (LMIT) was done on peripheral leukocytes. Local antispermatic activity in the cervical mucus was negative in all PCT positive cases, and positive in 6 out of 11 PCT negative cases. SIT and STT were both positive in cervical mucus and in blood in one case only. No correlation could be found between PCT and serum SIT, STT or LMIT. The fertility pattern expressed by the number of pregnancies per years of exposure, already low in the whole group, was even lower in the sub groups with positive immunological factors. Positive immunological factors do not exclude the possibility of conception but appear to be associated with a reduced rate of conception.