Between July and November 1991, 32 women (mean age 24.8 years) were examined laparoscopically in our department for suspected tubal sterility. All women had smears taken from cervix, vagina, and urethra, and all were negative regarding an infection with Chlamydia trachomatis. All women had open fallopian tubes, however, with inflammatory changes that varied in degree. Fifteen women reported pains and were classified as PID (pelvis inflammatory disease)-positive, as compared to the PID-negative group of 17 women without pain. In the group of the 15 PID-positive women, we could detect Chlamydia trachomatis in the form of salpingitis in 11 cases in the direct demonstration of the infectious agent. IgA antibodies were detected in the serum of all of these women, in 12 of them IgA + IgG antibodies. In the group of the 17 PID-negative women, three were positive in the direct detection of the infectious agent, and IgA and/or IgG antibodies were detected in five cases. 38% of the women in the PID-positive group and 68% in the PID-negative group conceived within a period of one year after having completed a treatment with antibiotics.