Maternal smoking, genes and adolescent brain and body: The Saguenay Youth Study
The prevalence of cigarette smoking in pregnant women varies widely in diﬀerent countries (Ebrahim, Decouﬂe, & Palakathodi, 2000; Kendrick & Merritt, 1996). In the United States, for example, the average prevalence was 16.3% in 1984 and decreased to 11.8% in 1994 (Ebrahim, Decouﬂe, & Palakthodi, 2000). In England, maternal smoking during pregnancy is less common (10%, The Stationery Oﬃce, 2002). In Canada, 25% of women aged 15 years and above are current smokers; of these, 58% smoked during their most recent pregnancy (Health Canada, 1995). In the National Longitudinal Study of Children and Youth (Canada), 23.7% of mothers reported smoking cigarettes during pregnancy (Connor & McIntyre, 1998); the highest prevalence of prenatal exposure to maternal cigarette smoking (PEMCS) was found during teenage pregnancies (50%). In Quebec, we found that 25% of expectant mothers smoked cigarettes throughout pregnancy and that 24% reported smoking daily 5 months after giving birth; these ﬁndings are based on a population sample of 2300 mothers who gave birth during 1997-1998 (Japel, Tremblay & McDuﬀ, 2000).