Mild COVID During Pregnancy Does Not Slow Brain Development in Babies

Summary: Babies of mothers who contracted mild or asymptomatic COVID-19 during pregnancy showed similar brain development to those born of mothers who did not contract coronavirus during pregnancy.

Source: Columbia University

Columbia researchers have found that babies born to moms who had mild or asymptomatic COVID during pregnancy are normal, based on results from a comprehensive assessment of brain development.

The findings expand on a smaller study that used maternal reports to assess the development of babies born in New York City during the first wave of the pandemic. That study found no differences in brain development between babies who were exposed to COVID in utero and those who were not exposed.

For the new study, the researchers developed a method of observing infants remotely, adapting a developmental assessment tool that is typically administered in person to make the study COVID-safe (babies were assessed between March 2021 and June 2022). 

The researchers studied 407 infants between 5 and 11 months of age from three geographic areas: New York City, Salt Lake City, Utah, and Birmingham, Alabama. Overall, nearly a third of the infants were born to mothers who had COVID during pregnancy.

Before the evaluation, each of the participating families received the same set of baby toys and food items so that the researchers could observe and compare the babies’ fine and gross motor skills in a standardized fashion. The researchers also assessed cognitive and language skills. They did not know which babies had been exposed to COVID in utero.

“The idea for our novel method to assess development remotely came from Columbia clinicians who quickly began performing telehealth visits at the start of the pandemic in an effort to continue to deliver high-quality care in safe ways,” says study leader Dani Dumitriu, MD, PhD, assistant professor of pediatrics and psychiatry at Columbia University Vagelos College of Physicians and Surgeons.

This shows a pregnant woman
That study found no differences in brain development between babies who were exposed to COVID in utero and those who were not exposed. Image is in the public domain

“But over time, we also realized that evaluating the babies remotely would allow us to observe how the babies were developing in their home environment, which may actually offer a better idea of how the infants are developing than when we see them in the research lab, where they may be scared or anxious.”

The researchers found that babies whose mothers had mild or asymptomatic COVID-19 at any point during pregnancy were developing similarly to those whose mothers had never had COVID.

“The current study, which used a more rigorous method to evaluate babies born during the pandemic, provides further reassuring evidence that having a mild or asymptomatic case of COVID during pregnancy does not affect brain development in infants,” Dumitriu says. “Additional studies are needed to tell us about the impact of more severe COVID on a developing infant’s brain.”

Funding: The study was funded by the U.S. Centers for Disease Control and Prevention (75D30120C08150) and the National Institutes of Health (R01MH126531).

About this neurodevelopment and COVID-19 research news

Author: Helen Garey
Source: Columbia University
Contact: Helen Garey – Columbia University
Image: The image is in the public domain

Original Research: Open access.
Assessment of Neurodevelopment in Infants With and Without Exposure to Asymptomatic or Mild Maternal SARS-CoV-2 Infection During Pregnancy” by Dani Dumitriu et al. JAMA Network Open


Assessment of Neurodevelopment in Infants With and Without Exposure to Asymptomatic or Mild Maternal SARS-CoV-2 Infection During Pregnancy


Associations between prenatal SARS-CoV-2 exposure and neurodevelopmental outcomes have substantial public health relevance. A previous study found no association between prenatal SARS-CoV-2 infection and parent-reported infant neurodevelopmental outcomes, but standardized observational assessments are needed to confirm this finding.


To assess whether mild or asymptomatic maternal SARS-CoV-2 infection vs no infection during pregnancy is associated with infant neurodevelopmental differences at ages 5 to 11 months.

Design, Setting, and Participants  

This cohort study included infants of mothers from a single-site prospective cross-sectional study (COVID-19 Mother Baby Outcomes [COMBO] Initiative) of mother-infant dyads and a multisite prospective cohort study (Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2 in Pregnancy and Infancy [ESPI]) of pregnant individuals. A subset of ESPI participants was subsequently enrolled in the ESPI COMBO substudy. Participants in the ongoing COMBO study were enrolled beginning on May 26, 2020; participants in the ESPI study were enrolled from May 7 to November 3, 2021; and participants in the ESPI COMBO substudy were enrolled from August 2020 to March 2021. For the current analysis, infant neurodevelopment was assessed between March 2021 and June 2022. A total of 407 infants born to 403 mothers were enrolled (204 from Columbia University Irving Medical Center in New York, New York; 167 from the University of Utah in Salt Lake City; and 36 from the University of Alabama in Birmingham). Mothers of unexposed infants were approached for participation based on similar infant gestational age at birth, date of birth, sex, and mode of delivery to exposed infants.


Maternal symptomatic or asymptomatic SARS-CoV-2 infection.

Main Outcomes and Measures  

Infant neurodevelopment was assessed using the Developmental Assessment of Young Children, second edition (DAYC-2), adapted for telehealth assessment. The primary outcome was age-adjusted standard scores on 5 DAYC-2 subdomains: cognitive, gross motor, fine motor, expressive language, and receptive language.


Among 403 mothers, the mean (SD) maternal age at delivery was 32.1 (5.4) years; most mothers were of White race (240 [59.6%]) and non-Hispanic ethnicity (253 [62.8%]). Among 407 infants, 367 (90.2%) were born full term and 212 (52.1%) were male. Overall, 258 infants (63.4%) had no documented prenatal exposure to SARS-CoV-2 infection, 112 (27.5%) had confirmed prenatal exposure, and 37 (9.1%) had exposure before pregnancy or at an indeterminate time. In adjusted models, maternal SARS-CoV-2 infection during pregnancy was not associated with differences in cognitive (β = 0.31; 95% CI, −2.97 to 3.58), gross motor (β = 0.82; 95% CI, −1.34 to 2.99), fine motor (β = 0.36; 95% CI, −0.74 to 1.47), expressive language (β = −1.00; 95% CI, −4.02 to 2.02), or receptive language (β = 0.45; 95% CI, −2.15 to 3.04) DAYC-2 subdomain scores. Trimester of exposure and maternal symptom status were not associated with DAYC-2 subdomain scores.

Conclusions and Relevance  

In this study, results of a novel telehealth-adapted observational neurodevelopmental assessment extended a previous finding of no association between prenatal exposure to maternal SARS-CoV-2 infection and infant neurodevelopment. Given the widespread and continued high prevalence of COVID-19, these data offer information that may be helpful for pregnant individuals who experience asymptomatic or mild SARS-CoV-2 infections.

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