Study Title:

Folate During Pregnancy Reduces Future Risk for ADHD

Study Abstract

Background: Maternal nutrition during pregnancy has been linked with fetal brain development and psychopathology in the offspring. We examined for associations of maternal folate status and dietary intake during pregnancy with brain growth and childhood behavioural difficulties in the offspring.

Methods: In a prospective cohort study, maternal red blood cell folate (RCF) was measured at 14 weeks of pregnancy and total folate intake (TFI) from food and supplements was assessed in early and late pregnancy. The offspring's head circumference and body weight were measured at birth and in infancy, and 100 mothers reported on children's behavioural difficulties at a mean age of 8.75 years using the Strengths and Difficulties Questionnaire.

Results: Lower maternal RCF and TFI in early pregnancy were associated with higher childhood hyperactivity (RCF: beta = −.24; p = .013; TFI: beta = −.24; p = .022) and peer problems scores (RCF: beta = −.28; p = .004; TFI: beta = −.28; p = .009) in the offspring. Maternal gestational RCF was positively associated with head circumference at birth (adjusted for gestational age), and mediation analyses showed significant inverse indirect associations of RCF with hyperactivity/inattention and peer problems via fetal brain growth. Adjustment for mother's smoking and drinking alcohol during pregnancy did not change the results.

Conclusions: Although the associations are small and residual confounding is possible, our data provide preliminary support for the hypothesis that lower folate status in early pregnancy might impair fetal brain development and affect hyperactivity/inattention and peer problems in childhood.

From press release:

It has long been suggested that healthy folate (the natural form of folic acid) levels in expectant mothers goes hand in hand with healthy nervous system development in their children. A study published in an upcoming issue of The Journal of Child Psychology and Psychiatry finds that low maternal folate levels is linked to the development of attention-deficit/hyperactivity problems in children at age seven to nine years.

Researcher Dr. Wolff Schlotz points out, "Our findings further support the hypothesis that maternal nutrition contributes to an individuals' development, with potential consequences for their behavior later in life." The long term effects of poor maternal nutrition may even branch out to the child's ability to interact with peers or form social bonds.

The researchers also found that children born from mothers with a low folate status had a notably smaller head circumference at birth, which may indicate a smaller rate of prenatal brain growth in children adversely affected by low folate levels. This is a cause for concern among low-income populations where the nutritional health of the mother is a low priority, and women are less likely to take folate supplements in advance of pregnancy.

Study Information

Wolff Schlotz, Alexander Jones, David I.W. Phillips, Catharine R. Gale, Sian M. Robinson, and Keith M. Godfrey.
Lower maternal folate status in early pregnancy is associated with childhood hyperactivity and peer problems in offspring.
The Journal of Child Psychology and Psychiatry
2009 October
MRC Epidemiology Resource Centre, University of Southampton, UK.

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