Abstract
Introduction: Sexually transmitted infections (STIs) continue to increase in the United States and pregnant patients who acquire STIs are at risk for serious complications. This study estimated the utilization of preventative STI testing among pregnant outpatients on a national scale. Methods: This was a retrospective, cross-sectional study of outpatient visits in the National Ambulatory Medical Care Survey from 2014 to 2016 and 2018 to 2019. All patients reported as pregnant were included to assess STI testing for chlamydia, gonorrhea, hepatitis, and HIV. STI testing was described per 1,000 total visits overall and by subpopulations. Data weights were applied to generate national estimates. Results: Over 177 million visits were included, of which 87.5 per 1,000 included an STI test. Chlamydia testing was the most common, followed by HIV, gonorrhea, and hepatitis (58.0 vs. 42.3 vs. 41.5 vs. 20.3 per 1,000). STI testing rates varied across subpopulations (72.1-236.6 per 1,000 visits). Patients of Hispanic ethnicity, Black race, age ≤25 years old, and those seen by an obstetrics and gynecology (OB/GYN) provider had the highest rates of STI testing. Independent predictors of STI testing included: Black race (adjusted odds ratio [aOR]: 2.24, 95% confidence interval [95% CI]: 2.23-2.24), first trimester (aOR: 5.15, 95% CI: 5.14-5.16), government and private insurance (aOR: 1.90, 95% CI: 1.89-1.91 and aOR: 1.70, 95% CI: 1.69-1.71), and an OB/GYN provider specialty (aOR: 2.93, 95% CI: 2.93-2.94). Conclusions: STI testing in United States outpatient physician offices varied by subpopulations and across individual test types. Certain patient attributes, such as race, provider specialty, and payment source, were predictive of testing.