Methadone is a drug that is commonly used to treat opiate addiction, usually as part of a detoxification and maintenance program. Methadone offers significant therapeutic benefits to pregnant women who are opiate dependent, and it is currently the treatment of choice for this group of people. In general, breast milk is beneficial for infants. However, there is some concern as to whether it is safe for women who are taking methadone to breastfeed their babies. The purpose of this study is to determine the amount of methadone in the breast milk of women who are breastfeeding and taking methadone for opiate addiction. In addition, this study will evaluate the effects of methadone on infant neurobehavior.

Participants will be assigned to one of two groups: women taking methadone who will breastfeed their babies or women taking methadone who will bottle-feed their babies. On Days 1, 2, 3, 4, 14, and 30, following infant delivery, plasma will be collected from both groups and breast milk will be collected from the breastfeeding group. These samples will be quantitatively analyzed for methadone. Infants will undergo neurobehavioral assessments on Days 3, 14, and 30, following birth. Rates and severity of neonatal abstinence syndrome will also be evaluated.