Light drinking versus abstinence in pregnancy – behavioural and cognitive outcomes in 7‐year‐old children: a longitudinal cohort study

<jats:sec><jats:title>Objective</jats:title><jats:p>To assess whether light drinking in pregnancy is linked to unfavourable developmental outcomes in children.</jats:p></jats:sec><jats:sec><jats:title>Design</jats:title><jats:p>Prospective population‐based cohort.</jats:p></jats:sec><jats:sec><jats:title>Setting</jats:title><jats:p><jats:styled-content style="fixed-case">UK</jats:styled-content>.</jats:p></jats:sec><jats:sec><jats:title>Population</jats:title><jats:p>Ten thousand five hundred and thirty‐four 7‐year‐olds.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Quasi‐experimental using propensity score matching (<jats:styled-content style="fixed-case">PSM</jats:styled-content>) to compare children born to light (up to 2 units per week) and non‐drinkers.</jats:p></jats:sec><jats:sec><jats:title>Main outcome measures</jats:title><jats:p>Behavioural difficulties rated by parents and teachers; cognitive test scores for reading, maths and spatial skills.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Ordinary least squares (<jats:styled-content style="fixed-case">OLS</jats:styled-content>) regression and <jats:styled-content style="fixed-case">PSM</jats:styled-content> analyses are presented. For behavioural difficulties, unadjusted estimates for percentage standard deviation (<jats:styled-content style="fixed-case">SD</jats:styled-content>) score differences ranged from 2 to 14%. On adjustment for potential confounders, differences were attenuated, with a loss of statistical significance, except for teacher‐rated boys' difficulties. For boys, parent‐rated behavioural difficulties: unadjusted, −11.5; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, −4.3; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, −6.8; teacher‐rated behavioural difficulties: unadjusted, −13.9; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, −9.6; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, −10.8. For girls, parent‐rated behavioural difficulties: unadjusted, −9.6; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, −2.9; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, −4.5; teacher‐rated behavioural difficulties: unadjusted, −2.4; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 4.9; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 3.9. For cognitive test scores, unadjusted estimates for differences ranged between 12 and 21% of an <jats:styled-content style="fixed-case">SD</jats:styled-content> score for reading, maths and spatial skills. After adjustment for potential confounders, estimates were reduced, but remained statistically significantly different for reading and for spatial skills in boys. For boys, reading: unadjusted, 20.9; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 8.3; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 7.3; maths: unadjusted, 14.7; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 5.0; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 6.5; spatial skills: unadjusted, 16.2; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 7.6; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 8.1. For girls, reading: unadjusted, 11.6; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, −0.3; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, −0.5; maths: unadjusted, 12.9; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 4.3; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 3.9; spatial skills: unadjusted, 16.2; <jats:styled-content style="fixed-case">OLS</jats:styled-content>, 7.7; <jats:styled-content style="fixed-case">PSM</jats:styled-content>, 6.4.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The findings suggest that light drinking during pregnancy is not linked to developmental problems in mid‐childhood. These findings support current <jats:styled-content style="fixed-case">UK</jats:styled-content> Department of Health guidelines on drinking during pregnancy.</jats:p></jats:sec>