Acute and chronic pain are often managed with drug therapy, which may include extended use of drug classes such as opioids and benzodiazepines. Pain does not go away, and may intensify during pregnancy. A woman who uses drugs (prescribed and/or non-prescribed) during pregnancy may expose her unborn child to compounds that could adversely affect neonatal development, may lead to premature delivery, and may precipitate a characteristic withdrawal syndrome called neonatal abstinence syndrome (NAS). In the United States, the Centers for Disease Control and Prevention has reported that among 28 states surveyed, the overall incidence of NAS increased by 300% from 1999 to 2013 (https://www.cdc.gov/mmwr/volumes/65/wr/mm6531a2.htm). A pregnant woman that has a known addiction to opioids may be managed with opioid substitution agents such as buprenorphine or methadone, which may reduce the incidence and severity of NAS. Nonetheless, treatment of NAS may require several weeks of intensive care for the newborn, as well as extensive follow-up care and social management. As such, accurate and timely detection of in utero substance exposure is a critical component of pre- and post-natal care and can assure provision of appropriate medical and social services for the newborn, the mother, and the associated caregivers. Testing biological specimens for drugs is an important tool for detection and confirmation of drug exposure. This presentation will describe pros and cons of several specimen types used to monitor exposure to medications during pregnancy and after delivery. Common analytical methods and challenges with interpretation of results will also be discussed.