Summary:
A prospective longitudinal study by researchers at Oregon Health & Science University (OHSU) published in Developmental Psychology demonstrates that supplemental vitamin C intake during pregnancy acts as a low-cost, modifiable buffer against the adverse neurodevelopmental effects of maternal stress.
Evaluating more than 300 mother-infant pairs, the research team found that maternal prenatal stress significantly depleted dietary vitamin C intake, which subsequently predicted elevated negative emotionality, such as frequent fussiness and distress, in infants at six months of age. Supplemental vitamin C significantly mediated this risk, pointing to an accessible nutritional intervention to support fetal brain development.
Key Facts:
- Stress-Nutrition Depletion: High maternal psychological stress during pregnancy directly correlated with lower dietary vitamin C intake; approximately 25% of pregnant women in the United States already consume less than the recommended daily allowance.
- Predictor of Negative Emotionality: Offspring of mothers experiencing high prenatal stress and low vitamin C intake exhibited significantly higher rates of negative emotional reactivity and distress at six months of age, an early behavioral risk marker for later psychiatric disorders.
- Supplementation as a Protective Buffer: Daily supplemental vitamin C intake during pregnancy functioned as a statistically significant mediator, mitigating the impact of maternal stress on infant temperament and emotional regulation.
Source: Oregon Health & Science University / APA
A mother’s physiological and psychological state during pregnancy fundamentally sculpts the fetal intrauterine environment. While decades of epidemiological research have established how prenatal conditions shape cardiometabolic trajectories, emerging developmental neurobiology reveals that maternal stress and nutritional status exert equally potent influences over embryonic and fetal brain assembly.
Maternal prenatal stress often exerts a compounding toll on nutritional health, altering metabolic demands while contributing to dietary deficits in essential micronutrients. Among these, vitamin C (ascorbic acid) serves vital anti-oxidative and neuromodulatory roles, supporting neurogenesis, collagen synthesis in cerebral vasculature, and catecholamine regulation. Despite its biological importance, roughly 25% of pregnant women across the United States fail to reach the recommended dietary threshold, with fresh fruit and vegetable access frequently constrained by socioeconomic boundaries and food insecurity.
Now, an investigation published in the American Psychological Associationโs journal Developmental Psychology demonstrates that targeted nutritional support can counteract stress-driven neurodevelopmental vulnerability. Led by clinician-researchers at Oregon Health & Science University (OHSU), the study reveals that supplemental vitamin C during pregnancy can safeguard infant socioemotional health.
Tracking Over 300 Mother-Infant Pairs
The OHSU research team enrolled more than 300 pregnant women to evaluate the complex interactions among maternal mental health, dietary intake, and offspring neurodevelopment.
The study protocol utilized a multi-stage prospective design:
- Maternal Psychiatric Profiling: Participants were assessed during pregnancy using standardized clinical screening batteries evaluating depression, anxiety, and perceived psychological stress.
- Dietary vs. Supplemental Tracking: Registered dietitians conducted repeated nutritional recall interviews with participants to quantify micronutrient consumption, distinguishing between dietary vitamin C derived from whole foods and supplemental intake from daily prenatal vitamins or tablets.
- Infant Temperament at Six Months: When infants reached six months of age, primary caregivers completed standardized temperament assessments measuring behavioral reactivity, consolability, distress, and negative emotionality in their home environments.
The resulting data demonstrated a clear pathway: pregnant women reporting elevated psychological stress consumed lower amounts of dietary vitamin C. In turn, lower maternal vitamin C levels significantly predicted higher negative emotionality in infants at six months of age, marked by pronounced irritability, frequent crying, and difficulty soothing.
In developmental psychology, heightened negative emotionality in early infancy is recognized as a sensitive early behavioral marker associated with increased lifetime vulnerability to anxiety, depressive disorders, and behavioral dysregulation.
Supplemental Ascorbic Acid as a Protective Mediator
Encouragingly, statistical mediation analyses revealed that supplemental vitamin C intake significantly altered this trajectory. For mothers navigating high prenatal stress, taking supplemental vitamin C buffered their infants against negative emotional outcomes, neutralizing the developmental penalty observed in unsupplemented, stressed cohorts.
โA strong body of research shows that the intrauterine environment shapes cardiometabolic health. Weโre now learning how it also influences brain development and infant behavioral health,โ said lead author Elizabeth Wood, PhD, assistant professor of psychiatry in the OHSU School of Medicine. โOur top priority is the health of the pregnant woman and her baby. If there are evidence-based recommendations we can make to support patients during pregnancy and promote healthy brain development in their babies, thatโs something we want to pursue and make widely accessible.โ
Senior author Elinor Sullivan, PhD, professor of psychiatry and behavioral neuroscience at OHSU, highlighted the clinical feasibility of the findings:
โThe most encouraging takeaway here is that nutrition is relatively modifiable, especially when people have adequate resources and support,โ Sullivan said. โVitamin C supplements are inexpensive, easy to access and something patients can start incorporating immediately and consistently into their daily lives. This seemingly small change could make a huge impact for children and families down the line.โ
Expanding Clinical Guidance and Nutritional Equity
Because fresh, vitamin-rich produce remains financially out of reach for many low-income and rural families, the discovery that over-the-counter supplementation exerts protective neurodevelopmental effects provides a scalable avenue for clinical intervention.
OHSU clinicians are currently integrating these insights into frontline maternal care. The OHSU Center for Womenโs Health utilizes the “My Pregnancy Plate” framework alongside personalized nutritional counseling to assist expectant mothers in meeting daily micronutrient targets. Simultaneously, the Nourish program at OHSU Doernbecher Children’s Hospital partners with Portland Adventist Community Services to distribute fresh produce, pantry staples, and nutrient-dense groceries directly to patients experiencing food insecurity at the Maternal-Fetal Medicine Clinic.
The research team plans to follow this cohort longitudinally through childhood to establish whether prenatal vitamin C supplementation continues to mitigate psychiatric risk, attention deficits, and executive dysfunction across key developmental milestones.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this neurodevelopment Research:
- Media Contact:ย Nicole Rideout
- Source:ย Oregon Health & Science University
- Image Credit:ย Image credited to Neuroscience News
- Original Research is Open Access:ย Developmental Psychology (Nov 2, 2026). โPrenatal Vitamin C Supplementation Mediates the Association Between Prenatal Distress and Infant Negative Affect: A Prospective Cohort Study.โ Authors: Elizabeth K. Wood, Hailey E. Volk, Elizabeth K. Nousen, Olivia K. Nomura, Amanda N. Howery, Angela M. Horgan, Joel T. Nigg, Hanna C. Gustafsson, Elinor L. Sullivan.
- DOI:ย 10.1037/dev0002263
Abstract
Prenatal Vitamin C Supplementation Mediates the Association Between Prenatal Distress and Infant Negative Affect: A Prospective Cohort Study
Negative affect (NA) is a temperament trait reflecting the propensity to feel and express negative emotions. High NA in infancy is an early risk factor for future psychopathology and clinical diagnoses. Prenatal maternal depression, anxiety, and stress are linked to elevated infant NA, suggesting developmental programming effects. Given its antioxidative and stress-regulating properties, we investigated whether prenatal vitamin C mediates the association between maternal prenatal distress and infant NA.
Pregnant participants (N = 302; 73.2% White, non-Hispanic; Mage = 31.94 years, SD = 4.23 years) reported their prenatal vitamin C supplementation and completed three 24-hr dietary recalls from which dietary vitamin C intake was derived. Participants also completed assessments for prenatal depression (Center for Epidemiological StudiesโDepression and Edinburgh Postnatal Depression Scale), anxiety (State-Trait Anxiety Inventory and Beck Anxiety Inventory), and stress (Perceived Stress Scale).
Six months following delivery, infant NA was assessed via the Infant Behavior QuestionnaireโRevised. Confirmatory factor analysis supported a latent prenatal maternal distress variable, using prenatal scores from the Center for Epidemiological StudiesโDepression Scale, Edinburgh Postnatal Depression Scale, State-Trait Anxiety Inventory, Beck Anxiety Inventory, and Perceived Stress Scale as indicators.
Higher prenatal maternal distress predicted higher infant NA at 6 months (ฮฒ = .21, p = .001). Adjusting for covariates, structural equation modeling showed that prenatal vitamin C supplementation, but not dietary vitamin C intake, mediated the association between maternal prenatal distress and infant NA (indirect ฮฒ = .02, bootstrapped 95% conifidence interval [0.01, 0.05]).
As such, lower vitamin C intake during pregnancy may influence fetal neurodevelopment via altering the intrauterine environment. These findings point to prenatal vitamin C supplementationโs potential as a modifiable and scalable intervention to promote healthy early socioemotional development.
