Researchers at Oregon Health & Science University have found evidence that sensitive caregiving during the first months of life may protect children from the developmental effects of inflammation experienced before birth. In a study of more than 300 pregnant individuals and their children, elevated inflammation during pregnancy was associated with increased attention-deficit/hyperactivity disorder symptoms in early childhood—but only among children who received lower-than-average levels of responsive caregiving. The findings suggest that the postnatal environment may help shape how prenatal biological risks influence the developing brain.
The study, published in the Journal of Child Psychology and Psychiatry, is the first to investigate whether inflammation during gestation is connected to a child’s later ADHD presentation and whether early caregiving can modify that relationship. ADHD is a neurodevelopmental condition involving persistent patterns of inattention, hyperactivity or impulsivity. Although genetic factors account for a substantial portion of ADHD risk, researchers increasingly view the condition as the result of complex interactions between inherited susceptibility and environmental influences affecting brain development before and after birth.
Inflammation during pregnancy can be triggered by infection, chronic stress, smoking, metabolic dysfunction and other physiological challenges. In moderate and well-regulated amounts, inflammation is an essential part of the immune system’s response to danger. However, persistent or excessive activation of inflammatory pathways can alter the biological environment surrounding a developing fetus. Inflammatory molecules circulating in the mother’s blood may influence the placenta, affect nutrient and oxygen delivery, and modify signals involved in fetal brain development. These changes may influence neural circuits that later contribute to attention regulation and impulse control.
To examine this possibility, the OHSU research team drew on data from a prospective cohort study that followed pregnant participants and their offspring over time. Blood plasma samples collected during the second trimester were analyzed for markers of inflammation. This stage of pregnancy is particularly important because the fetal brain is undergoing rapid structural and functional development, including the formation and refinement of neural networks that may be relevant to later ADHD-related behaviors.
The researchers then observed parent-child interactions when the children were six months old. Their assessment focused on sensitive caregiving, a measure of how accurately and consistently an adult notices, interprets and responds to an infant’s verbal and nonverbal signals. This can include recognizing when a baby is tired or distressed, responding promptly to vocalizations, maintaining warm eye contact and adjusting interaction in ways that match the child’s emotional state. At 36 months, the children’s ADHD symptoms were assessed using established developmental measures.
The results revealed a specific interaction between prenatal inflammation and early caregiving. Higher inflammation during pregnancy was associated with more ADHD symptoms in the early preschool years, but the association appeared only among children exposed to lower-than-average sensitive caregiving. Among children who experienced more responsive and emotionally attuned interactions, the relationship between gestational inflammation and ADHD symptoms was not detected. The pattern indicates that early caregiving may buffer, or partially offset, the behavioral effects associated with prenatal inflammation.
The researchers caution that the findings do not mean caregiving causes or prevents ADHD, nor do they suggest that parents are responsible for a child’s neurodevelopmental condition. The study identifies a statistical association in a relatively young group of children, and symptoms observed at age three do not necessarily predict a formal ADHD diagnosis later in life. Other influences—including genetics, sleep, nutrition, socioeconomic conditions, environmental exposures and broader family circumstances—may also contribute to developmental outcomes.
Instead, the results highlight the possibility that early relationships help regulate the biological systems through which prenatal risk factors affect the brain. Responsive interactions may support the development of stress-regulation networks, emotional control and executive functions, which include working memory, flexible thinking and the ability to direct attention. Repeated experiences of being understood and comforted can also shape infant physiological responses, potentially influencing the maturation of neural pathways involved in arousal and self-regulation.
OHSU scientists say the findings could eventually support a two-stage approach to reducing ADHD-related risk: interventions during pregnancy that address chronic inflammation, combined with programs after birth that strengthen caregiver-child relationships. Potential prenatal strategies under investigation include fatty acid supplementation and mindfulness practices, although these approaches require further testing before they can be recommended as specific treatments for preventing ADHD. After birth, existing evidence-based programs can help caregivers practice play, shared reading, warm communication and prompt responses to children’s cues.
The researchers emphasize that responsive caregiving does not require a perfect parenting style or constant attention. Small, repeated moments of connection—smiling at a baby, responding calmly to a sound, joining a child in play or offering comfort during distress—may contribute to a supportive developmental environment. The broader challenge, they say, is ensuring that families have access to practical guidance, healthcare and social support during pregnancy and the transition to parenthood. If confirmed in larger and longer studies, the findings could help shift ADHD prevention research toward an integrated model in which prenatal biology and early childhood relationships are treated as connected parts of brain development.
Subject of Research:
The relationship between inflammation during pregnancy, sensitive early caregiving and ADHD symptoms in young children.
Web References:
OHSU Center for Mental Health Innovation: https://www.ohsu.edu/school-of-medicine/center-mental-health-innovation
References:
Journal of Child Psychology and Psychiatry study: https://doi.org/10.1111/jcpp.70200
Keywords:
ADHD, attention-deficit/hyperactivity disorder, gestational inflammation, pregnancy, fetal brain development, sensitive caregiving, early childhood, neurodevelopment, parenting, child mental health, OHSU
