Is Low Birth Weight Linked to Child Aggression?

Although advances in neonatal care over the past century have resulted in increased rates of survival among at-risk births, including infants with low birth weight, we have much to learn about psychological outcomes in this population. In particular, despite growing evidence that low birth weight may be associated with an increased risk for Attention-Deficit/Hyperactive Disorder (ADHD) symptoms in childhood, few studies have examined birth weight as a risk factor for disruptive disorders that commonly co-occur with ADHD. In addition, the etiology of the relation between birth weight and these disorders is unknown. A study published in the Journal of Abnormal Psychology aimed to better understand these associations in the context of potentially confounding genetic and environmental influences by examining phenotypic associations between birth weight and disruptive disorder symptoms both between families and within families in two independent twin samples (Sample 1: N = 1,676 individuals; Sample 2: N = 4,038 individuals). The researchers found negative associations between birth weight and inattentive, hyperactive-impulsive, and broad externalizing symptoms in both samples. Nonetheless, the overall magnitude of these associations was very small, contributing to less than 1% of the variance in these symptom dimensions. Within-family associations between birth weight and disruptive disorder symptoms did not differ for monozygotic and dizygotic twin pairs, suggesting that nonshared environmental influences rather than common genetic influences are responsible for these associations. Overall, the consistent albeit weak associations between birth weight and disruptive disorder symptoms suggest that low birth weight may not represent a major risk factor in the development of these symptoms.

For the abstract


Related Stories

  • Can Electric Shock Erase Unpleasant Memories?
  • Psychology, Law, and Same-Sex Parenting
  • Painfully Shy


The information provided on the is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her health professional. This information is solely for informational and educational purposes. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Neither the owners or employees of nor the author(s) of site content take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading this site. Always speak with your primary health care provider before engaging in any form of self treatment. Please see our Legal Statement for further information.

PsyWeb Poll

Are you currently taking or have you ever been prescribed anti-depressants?
Total votes: 3979