The value of Chlamydia trachomatis antibody testing in predicting tubal factor infertility.

BACKGROUND The objective of the present study was to compare the likelihood of abnormal Chlamydia trachomatis antibody test results with that of abnormal hysterosalpingography (HSG) test results in patients with tubal factor infertility. METHODS Anti-C. trachomatis immunoglobulin G antibodies were determined prospectively in 295 infertility patients by means of an indirect fluorescent antibody technique. In 48 of the 295 patients both HSG and laparoscopy with chromotubation were performed. The results of C. trachomatis antibody testing were compared with the results of HSG with respect to their predictive value of tubal factor infertility. Likelihood ratios for abnormal C. trachomatis antibody and HSG test results were determined in infertility patients, as assessed by laparoscopy. RESULTS The positive likelihood ratio for C. trachomatis antibody testing was 1.8. This was comparable with the HSG, which had a positive likelihood ratio of 1.7. CONCLUSIONS The predictive value of C. trachomatis antibody testing was equal to that of HSG, but ratios of 1.7 and 1.8 indicate a poor test, so both C. trachomatis antibody testing and HSG have a poor predictive value. C. trachomatis antibody testing causes minimal inconvenience to the patient, in contrast to HSG, and therefore should be maintained in infertility examinations.