Offspring of mothers who were smoking 1–10 cigarettes/day in pregnancy were at increased risk of being regular smokers at age 14 [OR(95%CI):2.04(1.49–2.79)] and heavy-smoker at age 31 [OR(95%CI):1.74(1.38–2.19)](Table 1). The same trend was observed for offspring of mothers smoking ≥10 cigarettes [OR(95%CI):1.84(0.90–3.76) for age 14 and 1.54(0.91–2.59) for age 31], although in this case differences were non-significant, probably because of the low number of heavily smoking mothers (N=96). The effect of maternal smoking during pregnancy became non-significant after adjusting for maternal smoking before pregnancy (Age 14:P=0.50; Age 31:P= 0.59).
