The Burden of Human Papillomavirus and Chlamydia trachomatis Coinfection in Women: A Large Cohort Study in Inner Mongolia, China

Background: Chlamydia trachomatis may coinfect with human papillomavirus (HPV) and complicate the cervical pathogenesis. This study aimed to evaluate the prevalence, risk factors, and clinical outcomes of HPV/C. trachomatis coinfection in women from Inner Mongolia, China. Methods: We performed a polymerase chain reaction (PCR)-based HPV/C. trachomatis screening and cervical samples were analyzed by thinprep cytologic test. Statistical analysis was used to assess the association between demographic factors and coinfection. Results: Among the 2345 women recruited, the prevalences of HPV, C. trachomatis, and HPV/C. trachomatis coinfection were 36.0%, 14.3%, and 4.8%, respectively. The rate of multiple HPV genotypes was higher in coinfected women. HPV66 was the most frequently identified genotype in coinfected participants. The HPV DNA load was significantly higher in HPV monoinfected cases. In contrast, the DNA load of C. trachomatis was significantly higher in the coinfection group. Risk factors, including single women (odds ratio [OR] = 6.0, 95% confidence interval [CI], 4.044-8.782) and women with multiple sex partners (OR = 1.9, 95% CI, 1.324-2.824), were associated with coinfection. Importantly, coinfection was associated with increased risk for high-grade squamous intraepithelial lesions. Conclusions: HPV and C. trachomatis coinfection is an important risk factor for the progression of cervical lesions.