A study of children exposed to maternal COVID-19 before birth found no adverse neurodevelopmental outcomes by 2 years and a slight increase in parent-reported infant self-regulatory behavior—a generally positive finding—at 6 months.
A University of Calgary–led research team compared neurodevelopmental outcomes among 96 children prenatally exposed to SARS-CoV-2 infection in utero with those of 800 unexposed children during the first 2 years of life. Mothers reported on their children's temperament at ages 6 and 24 months and development and socio-emotional milestones at 12 and 24 months.
The children were part of the Canadian Pregnancy During the COVID-19 Pandemic cohort, which enrolled participants from April 2020 to July 2022. Nearly all children (99%) who had prenatal SARS-CoV-2 infection exposure confirmed by polymerase chain reaction had symptoms, 54% had persistent symptoms, and 5% were hospitalized.
The research was published yesterday in JAMA Network Open.
"Although vertical transmission of SARS-CoV-2 during gestation is rare, the accompanying systemic inflammatory response in pregnant individuals may interfere with fundamental neurodevelopmental processes that can increase children’s risk for neurodevelopmental difficulties," the researchers wrote.
A negligible link to child neurodevelopment
Among the 96 COVID-exposed children, the average gestational age at birth was 39.2 weeks, and 47% were boys. Among the 800 controls, the average gestational age at birth was 39.5 weeks, and 49% were boys.
These differences should be interpreted with caution as they are preliminary, and the sample and cell sizes are small.
In analyses of covariance adjusted for prepregnancy health conditions and socioeconomic status, in utero exposure to SARS CoV-2 was tied to more self-regulatory control at 6 months (difference in average score, 0.19).
"Greater regulatory ability at age 6 months is associated with better attentional ability and is generally considered a strength," the investigators wrote. "Although unexpected, this result may support research theorizing that in utero exposure to SARS-CoV-2 infection leads to accelerated maturation, as has been found for other adverse prenatal exposures like stress."
No other significant neurodevelopmental differences or differences by child sex, exposure status, or trimester and severity of infection were seen. In mixed models adjusted for the same covariates that aimed to assess outcome changes over time, prenatal SARS-CoV-2 exposure was not linked to adverse neurodevelopmental changes from ages 6 to 24 months.
"Prenatal exposure to SARS-CoV-2 infection had a negligible association with child neurodevelopment during the first 2 years of life," the study authors wrote. "These differences should be interpreted with caution as they are preliminary, and the sample and cell sizes are small. Follow-up research is warranted to determine whether these predominantly null effects persist into later childhood."
The team urged caregiver and teacher investment in activities that promote neurocognitive and social development, such as shared reading, to help offset the adverse effect of the pandemic on neurodevelopmental outcomes.
