J Child Psychol Psychiatry. 2016 May;57(5):575-84. doi: 10.1111/jcpp.12486. Epub 2015 Nov 21.

Moderate alcohol drinking in pregnancy increases risk for children's persistent conduct problems: causal effects in a Mendelian randomisation study.

Murray J¹, Burgess S², Zuccolo L^3,⁴, Hickman M³, Gray R⁵, Lewis SJ³.

Author information

1: Department of Psychiatry, University of Cambridge, Cambridge, UK.
2: Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
3: School of Social and Community Medicine, University of Bristol, Bristol, UK.
4: MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK.
5: National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK.

Abstract

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.