Chlamydia trachomatis-Specific Antibodies and In Vitro Fertilization Outcome

<b>Objectives</b>: <i>Chlamydia trachomatis</i> (CT) infection affects female fertility. The purpose of our study was to assess the association between serological and follicular fluid markers of CT infection and in vitro fertilization (IVF) success. <b>Methods</b>: This prospective multicenter cohort study included female patients undergoing an IVF procedure in Serbia. The IVF procedure was performed according to the standard protocol. Serum and follicular fluid samples were collected during IVF, and anti-major outer membrane protein (anti-MOMP) IgG and IgA were determined by the Enzyme-Linked Immunosorbent Assay (ELISA) test. <b>Results</b>: A significantly higher embryo implantation rate was detected among patients negative for antibodies in follicular fluid (OR (95% CI): 5.254 (1.055; 26.152)). There was a trend toward increased risk of IVF failure in patients positive for either IgG or IgA in follicular fluid, or positive for IgG in serum. Older age was associated with lower odds for successful implantation (OR (95% CI): 0.888 (0.820; 0.962)), biochemical pregnancy (OR (95% CI): 0.890 (0.817; 0.969)), and live birth (OR (95% CI): 0.906 (0.833; 0.985)). <b>Conclusions</b>: Our results suggest that the presence of chlamydial anti-MOMP IgG and IgA in the serum and follicular fluid of infertile women could be indicative of lower IVF success rate, and that advanced maternal age is associated with higher risk of IVF failure.