This study, which used a novel telehealth-adapted observational neurodevelopmental assessment, confirmed a previous finding that prenatal exposure to maternal SARS-CoV-2 infection had no association with infant brain development. The continued widespread prevalence of COVID-19 may make the finding comforting for pregnant individuals who experience asymptomatic or mild SARS-CoV-2 infections.
The study analyzed infant neurodevelopment scores of 407 infants aged five to 11 months on cognitive, gross motor, fine motor, expressive language, and receptive language domains.
Previous data on this topic relied on parental reporting. This study is the first to use standardized observational measures. That avoids the potential bias from parental reporting, such as parental stress during the height of the pandemic. The study included some mothers who were infected during pregnancy and some who weren’t. The mothers participated in one of two ongoing studies: the COVID-19 Mother Baby Outcomes [COMBO] Initiative or Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2 in Pregnancy and Infancy (ESPI).
The study's strengths include its geographically diverse cohort and the use of the telehealth-adapted neurodevelopmental assessment tool. The study's limitations include the relatively small sample size, the study's observational nature, and the limited age range of the infants. Unmeasured variables such as psychosocial factors may have affected the results. And since the mothers were asymptomatic or had mild COVID-19 cases, it’s not possible to generalize about any developmental effects of moderate or severe cases.
Few documented cases of SARS-CoV-2 transmission from mother to infant have been reported. This suggests fetuses have strong protection against infection. But there are other mechanisms, such as maternal immune activation, that can affect brain development. Assessing whether maternal COVID-19 affects infants in other ways required longitudinal follow-up of children born to individuals who had asymptomatic or mild cases of COVID-19 during pregnancy.
Further studies are needed to assess the long-term effects of prenatal SARS-CoV-2 exposure on infant brain development.