Developing Sentinel Surveillance for Chlamydia and Gonorrhea Using Test Results From Routine Screening During Pregnancy

Background: Interpretation of case-based surveillance of chlamydia and gonorrhea is limited by the lack of negative tests for comparison. We sought to develop a sustainable electronic health record (EHR)-based approach to disease surveillance in a sentinel population of pregnant persons. Methods: We conducted a 1-year assessment of sexually transmitted infections (STIs) in persons receiving at least 1 pregnancy-related visit within our university medical center. Data were obtained using EHR analytic structured query language code. Patients were categorized by whether they had an STI test during pregnancy and if screened, by the STI test results (positive or negative). We assessed screening and positivity by demographic using bivariate analyses. Predictors of a positive STI test were determined using logistic regression. Results: We identified 4553 persons who received pregnancy care from January 1 to December 31, 2021. Seventy-six percent (n = 3483) of persons were screened for an STI during pregnancy. Those who identified as white or had private insurance were less likely to have a chlamydia test. Among persons screened, Trichomonas was the most commonly detected STI (5%, 141/2698) followed by chlamydia (4%, 135/3456), and gonorrhea (0.7% 24/3468). Predictors of a positive STI test during pregnancy were Black race (adjusted odds ratio [aOR], 6.0; 95% confidence interval [95% CI], 4.2-8.7), 25 years or younger (aOR, 2.5; 95% CI, 1.9-3.3), and public insurance (aOR, 1.6; 95% CI, 1.2-2.1). Conclusions: We demonstrated that EHRs can be used to assess gonorrhea and chlamydia positivity. These methods could potentially be applied in other jurisdictions to improve the understanding of national STI surveillance.