The effect of alcohol binge drinking in early pregnancy on general intelligence in children

The effects of low to moderate prenatal alcohol exposure in early pregnancy on IQ in 5-year-old children

OBJECTIVE

To examine the effects of low to moderate maternal alcohol consumption during early pregnancy on children's intelligence (IQ) at age 5 years.

DESIGN

Prospective follow-up study.

SETTING

Neuropsychological testing in four Danish cities 2003-2008.

POPULATION

A cohort of 1628 women and their children sampled from the Danish National Birth Cohort.

METHODS

Participants were sampled based on maternal alcohol consumption during pregnancy. At 5 years of age, children were tested with the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R). Parental education, maternal IQ, maternal smoking in pregnancy, the child's age at testing, gender, and tester were considered core confounding factors, whereas the full model also controlled for maternal binge drinking, age, BMI, parity, home environment, postnatal smoking in the home, health status, and indicators for hearing and vision impairments.

MAIN OUTCOME MEASURES

The WPPSI-R.

RESULTS

No differences in test performance were observed between children whose mothers reported consuming between one and four or between five and eight drinks per week at some point during pregnancy, compared with children of mothers who abstained. For women who reported consuming nine or more drinks per week no differences were observed for mean differences; however, the risks of low full-scale IQ (OR 4.6; 95% CI 1.2-18.2) and low verbal IQ (OR 5.9; 95% CI 1.4-24.9) scores, but not low performance IQ score, were increased.

CONCLUSIONS

Maternal consumption of low to moderate quantities of alcohol during pregnancy was not associated with the mean IQ score of preschool children. Despite these findings, acceptable levels of alcohol use during pregnancy have not yet been established, and conservative advice for women continues to be to avoid alcohol use during pregnancy.

The effects of low to moderate alcohol consumption and binge drinking in early pregnancy on selective and sustained attention in 5-year-old children

OBJECTIVE

The aim was to examine the effects of low to moderate maternal alcohol consumption and binge drinking in early pregnancy on children's attention at 5 years of age.

DESIGN

Prospective follow-up study.

SETTING

Neuropsychological testing in four Danish cities 2003-2008.

POPULATION

A cohort of 1628 women and their children sampled from the Danish National Birth Cohort.

METHODS

Participants were sampled based on maternal alcohol consumption during pregnancy. At 5 years of age, the children were tested with the recently developed Test of Everyday Attention for Children at Five (TEACh-5). Parental education, maternal IQ, maternal smoking in pregnancy, the child's age at testing, gender, and tester were considered core confounding factors, whereas the full model also controlled the following potential confounding factors: maternal binge drinking or low to moderate alcohol consumption, age, body mass index (BMI), parity, home environment, postnatal smoking in the home, child's health status, and indicators for hearing and vision impairments.

MAIN OUTCOME MEASURES

TEACh-5 attention scores.

RESULTS

There were no significant effects on test performance in children of mothers drinking up to 8 drinks per week compared with children of mothers who abstained, but there was a significant association between maternal consumption of 9 or more drinks per week and risk of a low overall attention score (OR 3.50, 95% CI 1.15-10.68). No consistent or significant associations were observed between binge drinking and attention test scores.

CONCLUSIONS

The findings suggest an effect of maternal consumption of 9 or more drinks per week on attention functions in children, but the study detected no effects of lower levels of maternal consumption and no consistent effects of maternal binge drinking.

The effect of different alcohol drinking patterns in early to mid pregnancy on the child's intelligence, attention, and executive function

OBJECTIVE

To conduct a combined analysis of the estimated effects of maternal average weekly alcohol consumption, and any binge drinking, in early to mid pregnancy on general intelligence, attention, and executive function in 5-year-old children.

DESIGN

Follow-up study.

SETTING

Neuropsychological testing in four Danish cities 2003-2008.

POPULATION

A cohort of 1628 women and their children sampled from the Danish National Birth Cohort.

METHODS

Participants were sampled based on maternal alcohol consumption during early pregnancy. At age 5 years, the children were tested for general intelligence, attention, and executive function. The three outcomes were analysed together in a multivariate model to obtain joint estimates and P values for the association of alcohol across outcomes. The effects of low to moderate alcohol consumption and binge drinking in early pregnancy were adjusted for a wide range of potential confounding factors.

MAIN OUTCOME MEASURES

Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), the Test of Everyday Attention for Children at Five (TEACh-5), and the Behavior Rating Inventory of Executive Functions (BRIEF) scores.

RESULTS

Multivariate analyses showed no statistically significant effects arising from average weekly alcohol consumption or any binge drinking, either individually or in combination. These results replicate findings from separate analyses of each outcome variable.

CONCLUSIONS

The present study contributes comprehensive methodological and statistical approaches that should be incorporated in future studies of low to moderate alcohol consumption and binge drinking during pregnancy. Furthermore, as no safe level of drinking during pregnancy has been established, the most conservative advice for women is not to drink alcohol during pregnancy. However, the present study suggests that small volumes consumed occasionally may not present serious concern.

The effects of low to moderate alcohol consumption and binge drinking in early pregnancy on executive function in 5-year-old children

OBJECTIVE

To examine the effects of low to moderate maternal alcohol consumption and binge drinking in early pregnancy on children's executive functions at the age of 5 years.

DESIGN

Follow-up study.

SETTING

Neuropsychological testing in four Danish cities 2003-2008. Population A cohort of 1628 women and their children sampled from the Danish National Birth Cohort.

METHODS

Participants were sampled based on maternal alcohol drinking patterns during early pregnancy. When the children were 5 years old, the parent and teacher forms of the Behaviour Rating Inventory of Executive Function (BRIEF) were completed by the mothers and a preschool teacher. Parental education, maternal IQ, prenatal maternal smoking, the child's age at testing, and the child's gender were considered core confounding factors. The full model also included maternal binge drinking or low to moderate alcohol consumption, maternal age, parity, maternal marital status, family home environment, postnatal parental smoking, pre-pregnancy maternal body mass index (BMI), and the health status of the child.

MAIN OUTCOME MEASURES

The BRIEF parent and teacher forms.

RESULTS

Adjusted for all potential confounding factors, no statistically significant associations between maternal low to moderate average weekly consumption and BRIEF index scores were observed.In adjusted analyses, binge drinking in gestational week 9 or later was significantly associated with elevated Behavioural Regulation Index parent Scores (2.04, 95% CI 0.33–3.76), and with the risk of high scores on the Metacognitive Index assessed by the teacher (OR 2.06, 95% CI 1.01–4.23) [corrected].

CONCLUSIONS

This study did not observe significant effects of low to moderate alcohol consumption during pregnancy on executive functioning at the age of 5 years. Furthermore, only weak and no consistent associations between maternal binge drinking and executive functions were observed.