Maternal substance use during pregnancy is highly correlated with serious negative neurodevelopmental fetal and childhood/adolescent outcomes. Research has established maternal tobacco and alcohol use as having the most profound effect on children and adolescents, although the use of other substances such as cannabis (Fried, 2002) and cocaine has also been studied (Huizink & Mulder, 2006). Up to this point, the focus of research on maternal smoking and drinking during pregnancy has primarily been on externalizing and conduct/behavioral outcomes in the child (Fried et al., 1997; Streissguth et al., 1984; Millberger et al., 1996; Fergusson et al., 1993; Knopik, 2009; Knopik et al., 2005; Wakschlag et al., 1997; Weitzman et al., 1992; Rantakallio et al., 1992), including ADHD (Huizink & Mulder, 2006), oppositional defiant disorder, conduct disorder (Fergusson et al., 1998), and later substance abuse. However, findings from recent research have suggested a potential relationship between prenatal nicotine and alcohol exposure and internalizing problems caused by disruptions in neurobehavioral and cognitive development, potentially resulting in depression, generalized anxiety, impaired memory function, lower scores on arithmetic tasks (Batstra et al., 2003) deficits in verbal learning (Richardson et al., 2002; Cornelius et al., 2001), auditory, and visual-perceptual processing (Fried, 2002), as well as IQ decrements (Streissguth et al., 1998, 1990) and slower information processing speeds (Huizink & Mulder, 2006). Evidence also indicates that these adverse effects may persist into early and late adolescence (Wakschlag et al., 1997), resulting in subsequent impaired executive functioning (Huizink & Mulder, 2006), increased incidence of substance abuse (particularly smoking) (Ernst et al., 2001) or a predisposition to early onset of smoking in offspring (after intrauterine exposure to heavy smoking) (Huizink & Mulder, 2006; Ernst et al., 2001; Kandler et al., 1994; Cornelius et al., 2000; Buka et al., 2003). It is still unclear, however, whether these results provide sufficient evidence to suggest a cause-and-effect relationship or if the association is confounded by variables such as social background, child-rearing practices, maternal and family characteristics (Fergusson et al., 1998), or genetic factors.