Late preterm birth, maternal depression, and risk of preschool psychiatric disorders

Objective: Preterm children are at greater risk for psychiatric disorders, including anxiety disorders and attention-deficit/hyperactivity disorder (ADHD), than their term-born peers. Prior research has focused primarily on children born at early gestational ages. Less is known about the rate of psychiatric disorders among late preterm or early term children. In addition, whether a history of maternal depression also associated with prematurity has an impact on the risk for psychiatric disorders remains underexplored.

Method: Preschoolers between ages 3 and 6 years (N = 306) were recruited for a study examining preschool depression that included healthy and disruptive preschoolers. Preschoolers were placed in the following groups: late preterm (34-36 weeks, n = 39), early term (37-39 weeks, n = 78), and full term (40-41 weeks, n = 154). DSM-IV psychiatric disorders were assessed via the Preschool Age Psychiatric Assessment. Maternal history of psychiatric disorders was assessed using the Family Interview for Genetic Studies.

Results: Late preterm children had higher rates of any Axis I psychiatric diagnosis (odds ratio = 3.18, 95% confidence interval = 1.09-4.76) and of any anxiety disorder (odds ratio = 3.74, 95% confidence interval = 1.59-8.78) than full term children after adjusting for gender, ethnicity, family income, and IQ. There were no differences in rates of psychiatric diagnoses between early term and full term children. A history of maternal depression mediated the relationship between late preterm birth and anxiety disorders in preschoolers.

Conclusions: Late preterm children were at increased risk for anxiety disorders at preschool age. A history of maternal depression mediated this association. Findings confirm the extension of the risk of psychiatric disorders associated with prematurity to the late preterm group, and suggest that maternal depression may play a key role in this risk trajectory.