This research will track the longitudinal neurobehavioral development of the buprenorphine-exposed fetus across gestation through 1 month of age in an effort to determine the safety of this medication for use during gestation, the relationship between maternal physiologic changes due to buprenorphine administration and newborn functioning, and to determine potential fetal neurobehavioral markers that may predict Neonatal Abstinence Syndrome expression and infant neurobehavioral outcome. Comparisons to results from a similar project in methadone-exposed pregnancies will be made. This proposal seeks to advance the way the investigators inform the treatment of the opioid dependent woman during pregnancy and her infant after birth.