OBJECTIVES: To determine the prevalence of opioid use before, during, and after pregnancy and describe its use based on patient-specific characteristics. Determine secular trend of opioid use 2006 to 2014. MATERIALS AND METHODS: Retrospective cohort study. A large Upper Midwest integrated health care system and insurer. Female individuals age 10 to 50 years with a delivery diagnosis from July 1, 2006 through June 30, 2014. MAIN OUTCOME MEASURE: prevalence of opioid use before, during, and after pregnancy; description of opioid use during these time periods. RESULTS: From 11,565 deliveries among 9690 unique women, 862 (7.5%) deliveries were associated with significant opioid use. Significant opioid use was associated with single marital status, Cesarean section, Medicaid coverage, tobacco use, depression, anxiety, bipolar disorder, substance use disorder, nonopioid analgesic use, and referral to physical therapy, psychotherapy, or pain specialists. From 2006 to 2014 opioid use decreased from 9% to 6% before, during, and after pregnancy with a rate of change per year of -0.2%. DISCUSSION: Known risk factors including tobacco and alcohol use, mental health diagnoses, substance use disorder, or Medicaid enrollment may enable enhanced assessments and targeted interventions to reduce unnecessary prescribing and use of opioids among pregnant women and those who might become pregnant. Strategies to decrease opioid use during pregnancy should be considered by health care systems and health plans to reduce opioid prescribing in this patient population.