Background: Chlamydia trachomatis (CT) is a prevalent sexually transmitted infection, with an estimated 128 million new cases annually. While its high global prevalence, particularly in young people, and its often-asymptomatic nature are well-known, localized data, especially in high-risk populations, remains scarce. This study aimed to determine the seroprevalence of CT and its associated risk factors among patients at the Cité-Verte District Hospital in Yaoundé, Cameroon.

Methods: From March to July 2025, we conducted a cross-sectional study of 210 patients seeking care for urogenital issues or undergoing STI screening. Anti-Chlamydia trachomatis IgG antibodies were detected in blood samples using an ELISA kit to indicate past or chronic infection. Sociodemographic and clinical data were collected, and statistical analyses were performed using SPSS 25.0 to identify associations.

Results: The seroprevalence of C. trachomatis was high, with 23% (49/210) of participants testing positive. While a broader analysis of risk factors on a subsample of 74 participants didn't yield significant associations, an exploratory multivariate regression revealed a strong link between inconsistent condom use and CT positivity. Specifically, those who never used condoms had an 11-fold higher risk of infection (adjusted odds ratio [AOR] = 11.00; 95% CI: 1.50–17.00) compared to those who always used them. A history of a diagnosed STI also showed a suggestive association (AOR = 2.90; 95% CI: 0.40–16.10). The study also noted a higher prevalence in males (33.3%) than females (28.3%).

Conclusion: The high CT seroprevalence highlights a significant public health burden in this hospital-based population. The strong association with inconsistent condom use underscores the critical need for targeted public health campaigns promoting consistent condom use. Future research with larger sample sizes is needed to confirm these findings and better understand the behavioural determinants of CT infection.