Maternal pre-pregnancy obesity and risk for inattention and negative emotionality in children Alina Rodriguez 1,2,3 1 Department of Psychology, Uppsala University, Sweden; 2 Dept of Epidemiology and Public Health, Lifecourse Epidemiology, Imperial College, London, UK; 3 MRC Social Genetic Developmental Psychiatry Centre, Institute of Psychiatry, King’s College, London, UK Objective: This study aimed to replicate and extend previous work showing an association between maternal pre-pregnancy adiposity and risk for attention deficit hyperactivity disorder (ADHD) symptoms in children. Methods: A Swedish population-based prospective pregnancy–offspring cohort was followed up when children were 5 years old (N = 1,714). Mothers and kindergarten teachers rated children’s ADHD symptoms, presence and duration of problems, and emotionality. Dichotomized outcomes examined difficulties of clinical relevance (top 15% of the distribution). Analyses adjusted for pregnancy (maternal smoking, depressive symptoms, life events, education, age, family structure), birth outcomes (birth weight, gestational age, infant sex) and concurrent variables (family structure, maternal depres- sive symptoms, parental ADHD symptoms, and child overweight) in an attempt to rule out confounding. Results: Maternal pre-pregnancy overweight and obesity predicted high inattention symptom scores and obesity was associated with a two-fold increase in risk of difficulties with emotion intensity and emotion regulation according to teacher reports. Means of maternal ratings were unrelated to pre-pregnancy body mass index (BMI). Presence and duration of problems were associated with both maternal over and underweight according to teachers. Conclusions: Despite discrepancies between maternal and teacher reports, these results provide further evidence that maternal pre-pregnancy overweight and obesity are associated with child inattention symptoms and extend previous work by establishing a link between obesity and emotional difficulties. Maternal adiposity at the time of conception may be instrumental in programming child mental health, as prenatal brain development depends on maternal energy supply. Possible mechanisms include disturbed maternal metabolic function. If maternal pre-pregnancy obesity is a causal risk factor, the potential for prevention is great. Keywords: ADHD, emotion regulation, prenatal, overweight/obesity, longitudinal studies. Novel findings were recently reported showing high maternal pre-pregnancy body mass index (BMI; kg/ m 2 ), i.e., overweight and obesity, were associated with core symptoms of attention deficit hyperactivity disorder (ADHD) in school-age children (Rodriguez et al., 2008). Results were based on teacher reports of symptoms in over 12,000 children from three Nordic prospective cohorts (Rodriguez et al., 2008). Repli- cation and further understanding of this association is vital as inattention and hyperactivity are among the most common behavioral difficulties in children (Schonwald & Lechner, 2006). The potential for public health value is huge amidst the ‘obesity epi- demic’ (Hedley et al., 2004), if the association is causal. Several issues concerning the nature of the asso- ciation between maternal pre-pregnancy BMI and ADHD symptoms in children remain unresolved. First, maternal overweight is associated with a higher degree of distress (Dallman et al., 2003) and previous work shows a connection between maternal stress/distress during pregnancy and ADHD symptoms in children (Rodriguez & Bohlin, 2005; Van den Bergh, Mulder, Mennes, & Glover, 2005). Therefore, distress rather than maternal BMI may be the causal risk factor. Second, overweight may be related to ADHD symptoms through a common ge- netic pathway (Liu, Li, Yang, & Wang, 2008). Hence, the association between maternal pre-pregnancy BMI and child symptoms may be better accounted for by common genetic liability. Third, maternal pre- pregnancy BMI has been implicated in the pro- gramming of child weight (Gale et al., 2007). Some studies point to the possibility that child overweight and ADHD symptoms are associated (Lam & Yang, 2007). To date, it cannot be discerned whether the association between maternal pre-pregnancy BMI and child ADHD symptoms is mediated via the child’s own weight. Altered emotionality, i.e., deficits or excess in emotional responsiveness or regulation, has been associated with small birth size (Pesonen et al., 2006), although not all studies concur (Roza et al., 2008). A recent report found novel associations be- tween maternal obesity and risk for fetal growth restriction and preterm birth (Rajasingam, Seed, Conflict of interest statement: No conflicts declared. Journal of Child Psychology and Psychiatry 51:2 (2010), pp 134–143 doi:10.1111/j.1469-7610.2009.02133.x Ó 2009 The Author Journal compilation Ó 2009 Association for Child and Adolescent Mental Health. Published by Blackwell Publishing, 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA