New serological enzyme immunoassays (EIAs) were compared with microimmunofluorescence (MIF) as a "gold standard" to detect Chlamydia trachomatis antibodies in different groups of obstetrical, gynecological, and subfertile patients. There were no significant differences in seroprevalence rates, except for the group of C. trachomatis-positive patients (P < 0.01). Test characteristics were calculated for Chlamydia-EIA (Biologische Analysensystem GmbH, Lich, Germany) and pELISA (Medac, Wedel, Germany). pELISA seems to be a good alternative to MIF. It has high specificity and is easier to perform.