Fetal alcohol exposure and children’s conduct problems

BACKGROUND: Heavy alcohol use during pregnancy can cause considerable developmental problems for children, but effects of light-moderate drinking are uncertain. This study examined possible effects of moderate drinking in pregnancy on children's conduct problems using a Mendelian randomisation design to improve causal inference. METHODS: A prospective cohort study (ALSPAC) followed children from their mother's pregnancy to age 13 years. Analyses were based on 3,544 children whose mothers self-reported either not drinking alcohol during pregnancy or drinking up to six units per week without binge drinking. Children's conduct problem trajectories were classified as low risk, childhood-limited, adolescence-onset or early-onset-persistent, using six repeated measures of the Strengths and Difficulties Questionnaire between ages 4-13 years. Variants of alcohol-metabolising genes in children were used to create an instrumental variable for Mendelian randomisation analysis. RESULTS: Children's genotype scores were associated with early-onset-persistent conduct problems (OR = 1.29, 95% CI = 1.04-1.60, p = .020) if mothers drank moderately in pregnancy, but not if mothers abstained from drinking (OR = 0.94, CI = 0.72-1.25, p = .688). Children's genotype scores did not predict childhood-limited or adolescence-onset conduct problems. CONCLUSIONS: This quasi-experimental study suggests that moderate alcohol drinking in pregnancy contributes to increased risk for children's early-onset-persistent conduct problems, but not childhood-limited or adolescence-onset conduct problems.The UK Medical Research Council (MRC) and the Wellcome Trust [grant number 092731] and the University of Bristol provide core support for ALSPAC. Genotype data used in this analysis was specifically funded by the Wellcome Trust [grant number 083506]. JM [grant number 089963/Z/09/Z] and SB [grant number 100114] are supported by the Wellcome Trust. LZ is supported by the MRC [grant number G0902144], and works in a Unit that receives funding from the MRC [grant number G0600705] and the University of Bristol. MH is supported by The National Institute for Health Research School for Public Health Research, the Centre for the Development and Evaluation of Complex Interventions for Public Health Improvement, which receives funding from the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council [grant number RES-590-28-0005], the MRC, the Welsh Assembly Government and the Wellcome Trust [grant number WT087640MA], under the auspices of the UK Clinical Research Collaboration, and NIH [grant number RO1 AA018333] and MRC [grant number MR/L022206/1] alcohol research grants.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1111/jcpp.1248