Research from Oregon Health & Science University's Center for Mental Health Innovation provides new evidence that the way caregivers interact with children when they're very young can protect against the negative effects of inflammation during pregnancy, including increased attention-deficit/hyperactivity disorder, or ADHD, symptoms in children.
Existing research has linked increased maternal inflammation during pregnancy — caused by factors like infection, impaired metabolic state, smoking and stress — with increased risk for ADHD in children. However, few studies have examined how the postnatal environment, including parenting approaches, may modify these prenatal effects.
The OHSU study, published today in the Journal of Child Psychology and Psychiatry, found that early sensitive caregiving — a term that describes the extent to which a caregiver notices, understands and responds to a child's non-verbal cues and emotional needs — appears to buffer children against these negative effects, reducing their risk for ADHD.
OHSU's study is the first to examine whether gestational inflammation is related to a child's future ADHD presentation, and whether their symptoms could be mitigated by caregiving behaviors in early childhood.
Data came from a prospective cohort of over 300 pregnant individuals and their offspring. The research team measured inflammation in blood plasma samples in the second trimester, a time in fetal brain development that is especially important for the development of ADHD risk factors. Parent-child interactions were then observed when children were six months old, and their ADHD symptoms were assessed at 36 months.
The analysis of these data found that increased gestational inflammation was associated with child ADHD symptoms during the early preschool years, but only when children experienced lower than average levels of sensitive caregiving.

"We know that genetics play a role in ADHD, but what this research demonstrates is that the early environment is also an important factor," said lead author Hanna Gustafsson, Ph.D., associate professor of psychiatry in the OHSU School of Medicine. "Fetal brain development and risk for ADHD are influenced by the prenatal environment. Yet brain development doesn't stop when a child is born; it continues throughout life and can be molded by children's experiences, their family relationships, and their community."
Results suggest that children at risk for ADHD may benefit from both prenatal interventions that decrease gestational inflammation and from postnatal interventions that support early caregiver-child relationships.
Connection, engagement
However, researchers emphasize that no single way of parenting is perfect, and their research isn't intended to be prescriptive; rather, it offers tangible guidance to support child mental health.

"There is so much pressure on new parents, yet societally we provide limited support and tools," said co-author Elinor Sullivan, Ph.D., professor of psychiatry and behavioral neuroscience in the OHSU School of Medicine. "This research demonstrates that small moments of engagement and emotional connection with your child can create a significant, life-long impact."
Sullivan said that evidence-based interventions that support responsive and engaged parent-child interactions already exist, but they need to be made more broadly available and better integrated into healthcare and social service infrastructure.
These programs suggest that adjustments for parents can be simple: taking a few moments out of the day to actively engage with a child via play; reading or other shared activities; providing a prompt response to children when they speak; speaking in a warm, calm tone of voice; and waving or smiling at the child.
Looking ahead, researchers will be examining interventions to reduce inflammation during pregnancy, including fatty acid supplementation and mindfulness practices. The team also highlighted that the Oregon Department of Human Services is working to provide relevant pregnancy and parenting resources to Oregonian caregivers.
"There's no playbook for parenting," Gustafsson said. "Supporting caregivers throughout the transition to parenthood will not only benefit children but also create healthier families and communities for generations to come."
This research is supported by the National Institutes of Health under National Institute of Mental Health grant numbers R01MH117177, R01MH124824, and K01MH120507, as well as the National Center for Advancing Translational Sciences grant number UL1TR002369. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.