In a recent study published in the journal JAMA Network Open, researchers assessed whether exposure to mild or asymptomatic maternal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections during the pregnancy impacted the neurodevelopment of the infant.
Study: Assessment of Neurodevelopment in Infants With and Without Exposure to Asymptomatic or Mild Maternal SARS-CoV-2 Infection During Pregnancy. Image Credit: OleksiiSynelnykov/Shutterstock.com
The impact of in-utero exposure to influenza, herpes simplex, and zika viruses on the neurodevelopment of infants has been widely studied.
Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, the long- and short-term impacts of prenatal exposure to maternal SARS-CoV-2 infections on the infant have been the focus of various studies.
While there have been very few cases of vertical transmission of SARS-CoV-2 from mother to fetus, maternal immune activation and other such mechanisms can alter the infant's neurodevelopment.
Although ongoing research such as the COVID-19 Mother Baby Outcomes (COMBO) initiative prospective study reported no alterations in the infant's neurodevelopment due to prenatal exposure to SARS-CoV-2, these studies were based on parent-reported scores for the developmental measures of the infant.
These results could be biased due to the lower exposure of the parents to other infants for comparison and parental stress during the pandemic.
About the study
The present study examined mother-infant dyads and pregnant individuals enrolled in two parallel studies — the COMBO initiative and the prospective cohort. The latter was the multisite Epidemiology of SARS-CoV-2 in Pregnancy and Infancy (ESPI) Network study by the United States (U.S.) Centers for Disease Control and Prevention (CDC).
All delivering patients enrolled in the two studies were tested for SARS-CoV-2 through either a polymerase chain reaction (PCR) test of nasopharyngeal swabs or a serological test for antibodies against the virus.
Infants were considered exposed if the mother had tested positive for SARS-CoV-2 on either of the two tests during pregnancy or at the time of delivery.
A manual review of the electronic health records was performed to assess whether the SARS-CoV-2 infection in the mother was symptomatic or asymptomatic and to determine the trimester of exposure and date of onset of the infection.
The infant's neurodevelopment was assessed using the second edition of the standardized Developmental Assessment of Young Children (DAYC-2), conducted through telehealth visits using online meeting platforms due to the stipulated social distancing conditions during the COVID-19 pandemic.
The assessments were conducted through interviews with the parents or caregivers, direct behavioral observations, and direct assessments by the research assistants.
The results confirmed previous findings that prenatal exposure of the infant to SARS-CoV-2 through maternal infection did not affect the infant's neurodevelopment.
The neurodevelopmental assessment evaluated scores in cognitive development, gross and fine motor skills, and receptive and expressive language. Additionally, the scores in all these domains were similar for infants that were prenatally exposed to SARS-CoV-2 and infants that were unexposed.
The trimester during which the mother contracted the SARS-CoV-2 infection was also not associated with changes in the DAYC-2 scores in any subdomains. The infant's exposure during any of the three trimesters to maternal SARS-CoV-2 infection was not associated with changes in DAYC-2 subdomain scores compared to unexposed infants.
Furthermore, the symptomatic or asymptomatic nature of the maternal SARS-CoV-2 infection was also not associated with any neurodevelopmental subdomains assessed in the DAYC-2.
The researchers did note that higher gross motor DAYC-2 scores were observed in infants exposed to asymptomatic SARS-CoV-2 infections through the mother, while exposure to symptomatic SARS-CoV-2 infection did not show a similar association.
The study examined the impact of prenatal exposure to symptomatic or asymptomatic SARS-CoV-2 infections during different trimesters on the infant's neurodevelopment.
Overall, the results suggested that exposure of the infant to SARS-CoV-2 infections during any trimesters, regardless of the symptomatic nature, was not associated with lower scores in any neurodevelopmental domains.
As the COVID-19 pandemic continues with the emergence of newer variants, these findings may help guide the care of pregnant individuals with mild or asymptomatic SARS-CoV-2 infections.