A comparison of common practices for identifying substance use during pregnancy in obstetric clinics

Substance use during pregnancy has been linked to adverse birth and other outcomes. Screening and intervention in the prenatal clinic are recommended, and reliance on patient reports or selective urine drug screening is inadequate. The aim of this prospective project was to determine substance use identification rates associated with common screening practices, compared to universal screening, among pregnant women seeking care at an urban, academic obstetric clinic.

Women attending their first prenatal visit (N = 275) completed a self-report questionnaire on lifetime and current substance use. A urine drug screening was also conducted, the results of which were not reported to providers. Participants' charts were reviewed to obtain the results of provider-ordered screens.

The sample was primarily African-American and Latino, with Medicaid insurance. Ten women (4.6%) reported current marijuana use, while more than double that number (n = 27; 11.6%) screened positive for marijuana via universal screening. The majority of women who screened positive via universal screening did not have a provider-ordered urine drug screening, and less than one-third (29.3%) of clinician-ordered screens were positive for at least one substance. Finally, 90% of women who reported they were using marijuana were not selected by providers for a screen.

Data demonstrate the high proportion of women using marijuana and the limitations of patient self-report and selective, nonroutine screening to identify substance use during pregnancy. Effective, standardized, clinic-wide strategies are needed to support providers in identifying pregnant women who use substances in order to increase the frequency of education and intervention.