Effects of in-utero opiate exposure: new paradigms for old questions

Abstract

The purpose of this paper is to present an overview of existing research on prenatal opiate exposure, identifying limitations of past work and in so doing provide a useful paradigm for contemporary investigations. Initial opiate exposure research in the 70's and early 80's typically employed a bi-variate approach with little or no attention to multiple confounding factors. By the mid-80's most researchers recognized that not only biological but social and environmental risk factors must be considered and began to call for a multi-factorial approach to investigate perinatal and developmental outcomes associated with prenatal opiate exposure. However, concurrent with this direction toward a multivariate approach, prenatal cocaine exposure became a priority and funding interest in the effects of opiates began to wane. Unfortunately, rather than employ the model emerging from the experience of opiate investigations, initial research directed at identifying effects of cocaine exposure often employed the same type of bi-variate approach, naive to the cumulative risks concomitant to maternal substance abuse. Subsequently, one is left with a sense of dejavu as researchers investigating the effects of prenatal cocaine exposure begin to recognize the complexity of delineating the effects of prenatal drug exposure and the need to address multiple confounding factors. It is within this context that an overview of existing research on prenatal opiate exposure will be presented with the hope that the limitations of the past can be used to construct a useful paradigm for the future. The underlying premise of this discussion will be that efforts to delineate the effects of prenatal exposure to illicit drugs need to be conducted within the context of maternal addiction and concomitant effects on both mother and infant.