['To evaluate the role of Chlamydia trachomatis-induced humoral and cell-mediated immune (CMI) responses in predicting tubal factor infertility (TFI).', 'Blood samples were taken from 88 women with TFI and 163 control women. C. trachomatis and chlamydial heat shock protein 60 (CHSP60)-specific immunoglobulin G (IgG) antibodies were analysed using enzyme-linked immunosorbent assay (ELISA) kits. Proliferative reactivity of peripheral blood mononuclear cells was studied in vitro against Chlamydia elementary body (EB) and recombinant CHSP60 antigens.', 'C. trachomatis-specific IgG antibodies were found more frequently (43.2 versus 13.5%), and the antibody levels were higher in the TFI cases than in the controls (P < 0.001). C. trachomatis EB-induced lymphocyte responses were positive in 81.8% of the TFI cases and 58.9% of the controls (P < 0.001). Similarly, CHSP60-induced lymphocyte responses were found in 45.5% of the TFI cases and 30.7% of the controls (P < 0.001). CHSP60 antibody test was the best single test predicting TFI. Compared to cases with all four markers negative, the estimated risk for TFI was 4.1 (95% CI 1.4-11.9) among those with one positive marker and 19.9 (95% CI 6.9-57.4) among those with three to four positive markers.'] Do chlamydia trachomatis and chlamydial heat shock protein 60-specific antibody and cell-mediated responses predict tubal factor infertility?