Background

Two previous studies using ALSPAC data have examined the association between prenatal alcohol exposure and educational perfomance at Key Stage 2 (the last year of primary school, aged 11 years approximately). One study contrasted maternal and paternal alcohol intake in pregnancy, and found that maternal binge drinking was associated with lower KS2 scores but paternal binge drinking was not, thus suggesting an intrauterine mechanism (Alati, 2013). In support of this, a second study found children of mothers whose genotype predisposed them to lower alcohol consumption during pregnancy had a better performance at KS2 than the children of mothers whose genotype predisposed to heavier drinking; a finding which suggests positive associations in observational studies between self-reported moderate alcohol intake in pregnancy and child's educational attainment are explained by residual confounding by factors associated with socio-economic position (Zuccolo, 2013).

Prenatal cannabis exposure has also been shown to have a negative effect on intellectual development at age 6 (Goldschmidt, 2008), resulting in lower educational attainment at age 14 years (Goldschmidt, 2012). This association has not previously been explored using ALSPAC data. Intrauterine exposure to tobacco smoke and child's IQ at 8 has been studies using ALSPAC; associations between maternal and paternal smoking and child's IQ were similar, suggesting any relationship between smoking in pregnancy and child's IQ may not explained by intrauterine exposure (Alati, 2008).

Aims

This proposed study would extend previous work to determine if any negative impact of intrauterine exposure to alcohol, cannabis or tobacco on educational attainment persists to Key Stage 4 (GCSEs, taken when aged 15-16 years). [The inclusion of cannabis as an exposure will depend on whether numbers are adequate].