Periconceptual and prenatal alcohol consumption and neurodevelopment at age two and five years.

Objective: Examine the association between alcohol consumption before and during pregnancy and neurodevelopmental outcomes in the offspring at two and five years.

Study Design: Retrospective analysis of a prospective longitudinal cohort; SCOPE-BASELINE. Data on pre-conception and prenatal alcohol consumption were obtained at 15 weeks' gestation and categorised as abstinent, occasional-low (1-7units/week) and moderate-heavy (≥8units/week). Binge drinking was defined as ≥6 units/session. Outcome measures (Child Behaviour Checklist and Kaufman Brief Intelligence Test) were obtained at two and five years. Linear regression examined an alcohol consumption and Child Behaviour Checklist and Kaufman Brief Intelligence Test relationship, adjusting for several potential confounders.

Results: Data on alcohol consumption was available for 1,507 women. Adjusted linear regression suggested few associations: pre-pregnancy occasional-low alcohol consumption was associated with lower log externalizing Child Behaviour Checklist scores (-0.264, 95% CI: -0.009, -0.520), while pre-pregnancy moderate-high levels of alcohol consumption was associated with lower Kaufman Brief Intelligence Test verbal standard scores (-0.034, 95% CI: -0.001, -0.068) and composite IQ scores (-0.028, 95% CI: -0.056, -0.0004) at five-years. In the first trimester, moderate-high levels of alcohol consumption was associated with lower internalizing Child Behaviour Checklist scores at two-years (-0.252, 95% CI: -0.074, -0.430). No significant associations were observed between number of binge episodes pre-pregnancy or binge drinking in the first trimester and Child Behaviour Checklist or Kaufman Brief Intelligence Test.

Conclusions: We did not find strong evidence of associations between pre-pregnancy and early pregnancy maternal alcohol consumption and adverse neurodevelopmental outcomes at age two and five years overall. Further research examining alcohol consumption (including binge drinking) beyond 15 weeks' gestation and subsequent neurodevelopmental outcomes is needed to examine the potential effect of alcohol consumption in later pregnancy.