Bajo uso de folato durante el embarazo asociado con hiperactividad y problemas en la niñez.

Journal of Child Psychology and Psychiatry 51:5 (2010), pp 594–602

doi:10.1111/j.1469-7610.2009.02182.x

Lower maternal folate status in early pregnancy is associated with childhood hyperactivity and peer problems in offspring
Wolff Schlotz,1,2 Alexander Jones,1,3 David I.W. Phillips,1 Catharine R. Gale,1 Sian M. Robinson,1 and Keith M. Godfrey1
1

MRC Epidemiology Resource Centre,University of Southampton, UK; 2School of Psychology, University of Southampton, UK; 3UCL Institute of Child Health, London, UK

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 behaviouraldifficulties 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 ageof 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 headcircumference 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 providepreliminary 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. Keywords: Fetal programming, folate, behavioural difficulties, fetal brain growth, hyperactivity, peer problems. Abbreviations: TFI: total folate intake; RCF: red cell folate.

The concept of developmentalprogramming states that adverse environmental events during sensitive periods of organ development trigger plastic responses that result in long-lasting functional alterations and influence risk for disease later in life (Barker, 2004). Adverse fetal environments shape fetal growth trajectories, and small size at birth adjusted for gestational age provides an indicator of prenatal adversity. There isaccumulating evidence that lower fetal growth within the normal range is associated with childhood behavioural difficulties in the offspring, particularly hyperactivity/inattention, conduct problems and total behavioural difficulties (Schlotz & Phillips, 2009). As head circumference is an indicator of brain volume (Bartholomeusz, Courchesne, & Karns, 2002) and fetal head growth reflects the developmentof the fetal brain, head circumference at birth might be used to examine whether prenatal adversity influences later behaviour through altered brain growth. This is supported by previous findings that head circumference at birth was a better predictor of hyperactivity/ inattention and total behavioural difficulties in childhood than birth weight (Lahti et al., 2006; Schlotz, Jones, Godfrey, &Phillips, 2008).
Conflict of interest statement: No conflicts declared.

Although these results suggest a lasting effect of an adverse prenatal environment, they do not indicate which specific factors were involved in producing the adverse fetal environment. Fetal size at birth is the result of a combination of many determinants, for example nutrition, smoking, drug use or psychosocial stress of the...