BackgroundAtrazine and other corn herbicides are routinely detected in drinking water. Two studies on potential association of atrazine with small-for-gestational-age (SGA) and preterm birth prevalence found inconsistent results. Moreover, these studies did not control for individual-level potential confounders.ObjectivesOur retrospective cohort study evaluated whether atrazine in drinking water is associated with increased prevalence of SGA and preterm birth.MethodsWe developed atrazine concentration time series for 19 water systems in Indiana from 1993 to 2007 and selected all births (n = 24,154) based on geocoded mother’s residences. Log-binomial models were used to estimate prevalence ratios (PRs) for SGA and preterm delivery in relation to atrazine concentrations during various periods of the pregnancy. Models controlled for maternal demographic characteristics, prenatal care and reproductive history, and behavioral risk factors (smoking, drinking, drug use).ResultsAtrazine in drinking water during the third trimester and the entire pregnancy was associated with a significant increase in the prevalence of SGA. Atrazine in drinking water > 0.1 μg/L during the third trimester resulted in a 17–19% increase in the prevalence of SGA compared with the control group (< 0.1 μg/L). Mean atrazine concentrations over the entire pregnancy > 0.644 μg/L were associated with higher SGA prevalence than in the control group (adjusted PR = 1.14; 95% confidence interval, 1.03–1.24). No significant association was found for preterm delivery.ConclusionsWe found that atrazine, and perhaps other co-occurring herbicides in drinking water, is associated with an increased prevalence of SGA, but not preterm delivery.

Summary. For medical reasons, encouraging women to stop smoking during pregnancy and post partum has high priority. Many smokers want to stop smoking but decline clinical treatment when it is offered. The aim of this study was to find a method which was accepted by a large number of smokers, had a high success rate and, at the same time, required little involvement from personnel. For one year, all pregnant smokers attending 13 of the 14 public health maternity clinics in Gothenburg for their first appointment were invited to participate in this study. Inclusion criteria were daily smoking, a gestational age of less than 12 weeks and ability to understand Swedish. A total of 745 women was registered, but 22 of them stopped smoking before the treatment. The remaining women were randomized to a treatment group (n = 492) and a control group (n = 231). Of the 492 women in the treatment group 417 (85%) accepted the idea of using the self‐help manual written especially for pregnant women and given to each woman in the treatment group by the obstetrician. Overall 10.4% of the treatment group stopped smoking up to 8 weeks after delivery compared with 5.2% of the control group (odds ratio 0.5, 95% CI 0.2–0.9). The ex‐smoking status was verified by measurement of thiocyanate in blood. The self‐help manual had a high acceptance rate and a success rate that was double the rate in the control group.