Maternal risk factors for term neonatal seizures: population-based study in Colorado, 1989-2003

Neonatal seizures in term infants are rare but have important potential implications for brain development. Risk factors for neonatal seizures in term infants have been less well defined than those among preterm infants. To evaluate the relationship between maternal risk factors and neonatal seizures in the first 72 hours of life in term infants, a case-control study using the Colorado Birth Certificate Registry was conducted. Term neonates in all hospitals in Colorado with and without seizures in the first 72 hours were studied. After adjusting for vaginal delivery in the setting of herpes infection and post-term delivery, preexisting diabetes in the mother (odds ratio 4.30, 95% confidence interval 1.64-11.27, P < .01) and fetal distress (odds ratio 5.88, 95% confidence interval 4.60-7.13, P < .0001) were independent risk factors for neonatal seizures in term infants. These findings are confirmatory of previous reports that maternal preexisting diabetes and fetal distress increase the risk of neonatal seizure in term infants. Although we cannot establish the pathophysiology of neonatal seizures from this analysis, hypoxic-ischemic brain injury and hypoglycemia in infants of diabetic mothers are known causes of neonatal seizures that can be represented in this analysis by fetal distress and maternal preexisting diabetes, respectively. Maternal diabetic vasculopathy can also be a contributing factor.