[Tobacco, alcohol, marijuana and pregnancy: which women are at risk?]

Substance use during pregnancy is an important health issue in view of the risks to the unborn child. Predictive factors related to risk behaviors need to be assessed in order to develop prevention strategies. This assessment can also elucidate the relationship between prenatal exposure to substances and the construction of social inequalities in health early in the life course.

This multicenter study was conducted in 14 maternity wards. Substance use was assessed by means of a self-administered questionnaire. Pregnancy outcomes were extracted from by birth registries.

The study included 2,617 women and 2,342 newborns (88.2%). There was a marked contrast between drinkers, who were older, and with a higher socioeconomic status (SES), and smokers, who were younger, with a lower SES. Two patterns of alcohol use were observed. Binge drinking at the beginning of the pregnancy was more likely to be reported by primiparous women who had discovered they were pregnant later than average. This pattern differed from that of low regular alcohol use throughout pregnancy, which was more often reported by multiparous women. One case of FAS was observed. After adjusting for several confounders, a lower birth weight was observed only for children of smokers. The higher SES of drinkers raises the question of the importance of alcohol, compared to tobacco, in the construction of social inequalities in health.

These results indicate the need for early and targeted interventions.