Differences in pregnant and non-pregnant women's alcohol and drug use, substance treatment need, and treatment receipt were examined using The National Survey of Drug Use and Health (2002-2006). Treatment need and receipt were defined by either self-report or DSM-IV criteria. Pregnant women were less likely to use alcohol and drugs than non-pregnant women. Among women who use drugs, pregnant women were more likely to need treatment (odds ratio (OR) = 1.92; 95% confidence interval (CI): 1.46, 2.52), however they were not more likely to receive treatment (OR = 0.90; 95% CI: 0.54, 1.51). Overall, there is an unmet need for treatment among reproductive-aged substance users.