title: Passive and active maternal smoking as measured by serum cotinine: the effect on birthweight.
abstract: To determine how maternal exposure to environmental tobacco smoke affects birthweight, maternal sera obtained from 3529 pregnant women around 27 weeks gestation were analyzed for cotinine, a metabolite of nicotine. Based on cotinine levels, nonsmokers were divided into those exposed to environmental tobacco smoke (2-10 ng/mL) and those unexposed (< 2 ng/mL), and smokers were divided into tertiles. Compared with unexposed nonsmokers' infants, infants of exposed nonsmokers averaged 45 g less (P = .28) after adjustment for confounders, and smokers' infants averaged 78, 191, and 233 g less for the first, second, and third cotinine tertiles, respectively. Birthweight decreased 1 g for every nanogram per milliliter of cotinine increase (P < .001).
authors.affiliation: Maternal and Child Health and Epidemiology Programs, School of Public Health, University of California-Berkeley 94720.
authors.forename: B
authors.initials: B
authors.lastname: Eskenazi
authors.forename: A W
authors.initials: AW
authors.lastname: Prehn
authors.forename: R E
authors.initials: RE
authors.lastname: Christianson
mesh_terms: D000704:Analysis of Variance; D001724:Birth Weight; D016009:Chi-Square Distribution; D003367:Cotinine / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D015999:Multivariate Analysis; D011247:Pregnancy; D011263:Pregnancy Trimester, Third / Q000097:blood; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution; D003367:Cotinine