INTRODUCTION: Pelvic Inflammatory Disease (PID) is associated with long-term sequelae including infertility, ectopic pregnancy, and tubo-ovarian abscess. Although the emergency department (ED) is a common healthcare entry point, the extent of its utilization is unknown. Our objectives are to estimate utilization trends, determine economic burden and investigate factors affecting admission rates of women with PID presenting to EDs in the United States. METHODS: A retrospective analysis using the Nationwide Emergency Department Sample was used to assess ED visits of women ≥18 years old, between 2010 and 2014 with a primary diagnosis of PID, defined by the International Classification Diagnosis, 9th version. SAS 9.4 was used to perform chi-square and Z-tests. Admission rates were assessed by age, payer information, hospital characteristics and household income. Total charges were also analyzed. RESULTS: PID related ED visits decreased from 118,552 to 93,965 from 2010 to 2014 (-20.74%, P<.001). Total charges increased from $3,133.54 to $4,507.24 per visit from 2010 to 2014 (P<.0001); $1.926 billion total. In 2014, admission rates increased with age; 7.91%, 11.71%, 21.28%, 37.27% and 59.78% for women ages 18-24, 25-34, 35-44, 45-54 and 55+, respectively (P<.0001). Uninsured patients had the lowest admission rate (8.98% vs Medicaid 12.57%, private 20.99%, Medicare 27.21%, P<.0001). Admissions rates were nearly double for the highest income quartile compared to the lowest (23.41% vs 12.18%, P<.0001). CONCLUSION: Although the number of PID related ED visits decreased from 2010 to 2014, a significant economic burden still exists. Admission rate disparities are concerning for health inequities based on insurance status and household income.