The clinical significance of antichlamydial antibodies (Chlam Ab) was determined in a total of 1303 subfertile couples consulting for infertility investigation and treatment. Median age of the women was 30 (range 22-44) years and of the men 33 (range 21-53) years. The median duration of infertility was 4 (range 1-21) years. All patients were asymptomatic for genital tract infection. A comprehensive infertility investigation included examination of the endocrine, cervical, and tubal factor, and semen analysis, antisperm antibody (ASA) testing, sperm-mucus interaction testing in vitro using a standardized protocol, and post-coital testing (PCT). Screening for Chlam IgG Ab was performed in serum of both partners, obtained at the same time. Simultaneous microbial cultures in genital secretions of both partners included a broad spectrum of potentially pathogenic bacteria. Elevated titres of Chlam IgG Ab as seromarker for previous infection were found in 20.8% of all women, and in 12.6% of men. Chlam Ab were significantly more frequent in partners of seropositive patients (in 51.8% of women with a Chlam Ab positive partner, compared to 15.8% of the other women). Microbial screening outcome was not significantly related to results of chlamydial serology in both partners. In women, elevated titres of Chlam Ab were significantly associated with a tubal factor, but were not related to reduced quality of the endocervical mucus (CM), including the in-vitro penetrability of the CM (using partners' or donors' spermatozoa). In males, Chlam Ab were not significantly related to the outcome of semen analysis, including screening for ASA (IgG and/or IgA) in semen, and several parameters of sperm functional capacity. After exclusion of couples with tubal disease, subsequent male fertility did not significantly differ in males with or without Chlam Ab. The results suggest that during basic infertility investigation, positive chlamydial serology as an easy screening procedure indicates a higher risk for a tubal infertility factor. However, in asymptomatic patients, Chlam IgG Ab in serum are not associated with a cervical factor or with the male factor, using several determinants for evaluation of semen quality including subsequent fertilizing capacity.
