Light drinking during pregnancy: still no risk for socioemotional difficulties or cognitive deficits at 5 years of age? Findings from the UK Millennium Cohort Study
- 1Department of Epidemiology and Public Health, University College London, London, UK
- 2Institute for Social and Economic Research, University of Essex, Colchester, Essex, UK
- 3National Perinatal Epidemiology Unit, University of Oxford, Oxford, UK
- 4Department of Psychology and Health Sciences Research Institute, University of Warwick, Coventry, UK
Background
We recently reported that light alcohol consumption during pregnancy was not associated with an increased risk of behavioural difficulties or cognitive deficits at 3 years of age. However, it is not clear whether these associations remain constant or change over time.
Objective
To examine the relationship between light drinking during pregnancy and the risk of socio-emotional problems and cognitive deficits at age 5 years.
Design and Setting
Data from sweeps 1 and 3 of the nationally representative prospective UK Millennium Cohort Study were used.
Comparison Groups
Cohort members were grouped according to mothers’ reported alcohol consumption during pregnancy: abstainer; light, not more than 1–2 units per week or per occasion; moderate, not more than 3–6 units per week or 3–5 units per occasion; heavy/binge, 7 or more units per week or 6 or more units per occasion.
Main Outcome Measures
At age 5 the Strengths and Difficulties Questionnaire (SDQ) and British Ability Scales (BAS) tests were administered during home interviews Behavioural problems were indicated by scores falling above defined clinically relevant cut-offs on the SDQ. Standardised scores for the BAS Naming Vocabulary, Pattern Construction and Picture Similarities scales were used.
Results
Boys and girls born to light drinkers were less likely to have high total difficulties (for boys 6.6 vs 10.0%, OR 0.65, for girls 4.2 vs 6.3%, OR 0.67) and hyperactivity (for boys 10.1 vs 13.7%, OR 0.72, for girls 5.5 vs 7.7%, OR 0.72) scores compared with those born to abstainers. For boys the association for total difficulties remained statistically significant in fully adjusted models. Boys born to light drinkers had higher mean cognitive test scores compared to those born to abstainers: Naming Vocabulary (58 vs 55), Picture Similarities (56 vs 55), and Pattern Construction (52 vs 50) and the differences for Naming Vocabulary and Picture Similarities remained statistically significant in fully adjusted models. Girls born to light drinkers compared to those born to abstainers had higher mean scores on the Pattern Completion sub-scale (53 vs 52) but this difference was attenuated in fully adjusted models.
Conclusions
At age 5 years cohort members born to mothers who drank up to 1–2 drinks per week or per occasion during pregnancy were not at increased risk of clinically relevant behavioural difficulties or cognitive deficits compared with children of abstinent mothers.
