Relation of Chlamydia trachomatis infections to ectopic pregnancy: A meta-analysis and systematic review

BACKGROUND: In a multitude of previous studies, Chlamydia trachomatis (CT) plays an important role in the occurrence of ectopic pregnancy (EP). However, the predictive value of CT infections in the occurrence of EP has not been estimated worldwide. We thus evaluated, by means of a meta-analysis, the current status of the association between CT infections with EP and the potential predictive value of CT infections in EP. METHODS: We evaluated studies performed between the database construction time and August 2018 published in PubMed, the Cochrane Library, EMBASE, and the Web of Science (SCI). The relationship between CT and EP was calculated based upon the predetermined entry criteria for control group selection and the original data. The related articles were analyzed using a random-effects model, and the heterogeneity of the studies was assessed using the I(2) index. Data were analyzed with the STATA 12.0 software. RESULTS: Twenty-five studies that recruited 11960 patients were included in the present meta-analysis, and the relation of CT infections with EP were assessed. The association between CT infections and EP risk showed an odds ratio (OR) of 3.03, with a 95% confidence interval (CI) of 2.37 to 3.89. Our results showed that there was a statistically significant difference between the intervention and control groups. The prevalence of CT infections in EP was then calculated by a subgroup analysis: African (OR, 2.22; 95% CI, 1.14–4.31), European (OR, 3.16; 95% CI, 2.10–4.47), North American (OR, 3.07; 95% CI, 1.78–5.31), and Asian (OR, 3.39; 95% CI, 1.95–5.90). CONCLUSIONS: From the results of numerous studies conducted on different continents, this meta-analysis showed a clear association between EP and prior CT infections, that is, CT infections increase the risk of EP occurrence.