Definitive quantification of the smoking effect on birthweight

As shown in 45,522 liveborn singletons, the decrease in birthweight associated with maternal smoking during pregnancy may be stated as 5.4 gm/cigarette/day in whites and 2.3 gm/cigarette/day in blacks. If confounding variables such as maternal weight and pregnancy weight gains are factored out, the apparent effects of cigarette smoking alone are reduced by no more than 17 %. New values for birthweights of the progency of nonsmoking mothers still reveal a difference between blacks and whites of 267 gm for boys and 261 gm for girls.

Key words:

• Smoking
• birthweight
• cigarette usage
• smoking effect