Maternal diet in late pregnancy linked to infant mental health

Maternal diet in late pregnancy linked to infant mental health | Image Credit: © New Africa - © New Africa - stock.adobe.com.

There is an association between maternal diet during the third trimester of pregnancy and mental health risks in offspring, according to a recent study published in Scientific Reports.¹

Study overview

The study assessed child behavioral outcomes based on maternal diet in both the second and third trimester. Results indicated shifts in infant temperament and behavioral trajectories from the consumption of foods that rapidly increase blood sugar level during pregnancy.

“These findings highlight opportunities to enhance nutrition during pregnancy and improve offspring outcomes by providing specific dietary targets and timepoints that can make a difference in infant behavioral health,” said Elizabeth Wood, PhD, lead author and assistant professor of psychiatry in the OHSU School of Medicine.

Research objectives and methodology

The study was conducted to determine the impact of prenatal maternal diet, dietary glycemic index (GI), adiposity, and insulin resistance on infant negative affect (NA), with NA defined as a range of negative emotions.² Data was obtained from an ongoing longitudinal study evaluating the impact of perinatal nutrition on infant neurodevelopment.

Exposure data included participant-reported dietary intake, an in-laboratory body composition assessment, and second- and third-trimester fasting blood samples. Infant temperament was reported through questionnaires completed by caregivers 6 months after birth. Emotional regulation, including NA, was also observed.

Study population and measurements

Pregnancies between 2018 and 2021 were included in the final analysis, with mothers reporting prenatal dietary intake during 6 unannounced recalls in the second and third trimester. These recalls were performed across a 2-week period, and daily GI values were calculated using the Nutrition Data System for Research software (NDSR, versions 2018–2020).

Body fat during the second and third trimester were assessed using the BodPod Body Composition tracking system (Life Measurement, Inc.). Participants were instructed not to fast and to avoid exercising in the 3 hours prior to testing.

Venipuncture was utilized to collect fasting blood samples, which were assayed for plasma glucose and insulin. Insulin resistance was reported as the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR).

The Still-Face Paradigm (SFP) measure was used to assess infant NA, while the Infant Behavior Questionnaire-Revised (IBQ-R) was used to assess maternal reports of infant NA. Covariates included maternal age, parity, race and ethnicity, prenatal stress, synthetic insulin use, prenatal vitamin use, and socioeconomic status.

Key findings

Significantly increased adiposity, dietary GI, and HOMA-IR values were observed in patients with gestational diabetes mellitus vs their nondiabetic counterparts. Additionally, these factors were higher in patients using synthetic insulin vs those not using synthetic insulin.

A positive association was reported between second-trimester HOMA-IR and infant NA at 6 months, alongside an association with infant fear from the IBQ-R rated by a caregiver. Additionally, a link was reported between caregiver rated infant sadness from the IBQ-R and increased third-trimester GI.

No other measures of infant NA were linked to second-trimester HOMA-IR, nor was second-trimester adiposity linked to infant NA. However, a significant association was reported between third-trimester dietary GI and observer-rated NA at 6 months.

Third-trimester dietary GI was also linked to infant sadness at 6 months based on caregiver report. However, an association with caregiver-reported infant fear was not found.

Implications for maternal nutrition

There was also no significant association between third-trimester adiposity or HOMA-IR with infant NA, showing third-trimester dietary GI as the factor most strongly influencing outcomes. These results indicated an impact from maternal dietary quality during pregnancy, especially the third trimester, on infant neurodevelopment.

“Developing targeted dietary interventions that involve exchanging high-GI foods for lower-GI replacements may be a feasible means of enhancing infant neurodevelopmental health and well-being,” investigators concluded.

References

1. Study confirms link between maternal diet, risk to infant behavioral health. Oregon Health & Science University. March 26, 2025. Accessed March 28, 2025. https://www.eurekalert.org/news-releases/1078391
2. Wood EK, Nomura O, Ablow JC, et al. Higher prenatal dietary glycemic index in the third trimester of pregnancy is associated with infant negative affect at 6 months. Scientific Reports. 2025;15. doi:10.1038/s41598-025-91886-0