Neurodevelopment in the First 2 Years of Life Following Prenatal Exposure to Maternal SARS-CoV-2 Infection.

Importance: The effects of prenatal exposure to SARS-CoV-2 infection on child development throughout the first 2 years of life are unknown.

Objective: To evaluate whether prenatal exposure to SARS-CoV-2 infection was associated with child neurodevelopmental outcomes during the first 2 years of life.

Design, Setting, And Participants: This cohort study used data from the longitudinal, population-based pan-Canadian Pregnancy During the COVID-19 Pandemic cohort, which recruited participants from April 2020 to July 2022. Children were categorized as exposed to prenatal SARS-CoV-2 infection if their birthing parent had a positive polymerase chain reaction test performed by a health authority or as a healthy negative comparison if their birthing parent did not have SARS-CoV-2 antibodies in their postpartum dried blood spot sample.

Exposure: Prenatal SARS-CoV-2 infection.

Main Outcomes And Measures: The birthing parent reported on their child's temperament at ages 6 and 24 months, developmental milestones at ages 12 and 24 months, and social-emotional milestones at ages 12 and 24 months.

Results: A total of 896 children were included, with 96 children who had been exposed to a prenatal SARS-CoV-2 infection (mean [SD] gestational age at birth, 39.20 [1.50] weeks; 45 [47%] male) and 800 were healthy negative comparisons (mean [SD] gestational age at birth, 39.47 [1.54] weeks; 388 [49%] male). In analyses of covariance adjusted for prepregnancy medical conditions and household socioeconomic status, prenatal exposure to SARS CoV-2 infection was associated with slightly higher regulatory control scores, indicating more regulation, at age 6 months (difference in means, 0.19 [95% CI, 0.02-0.36]; P = .03; ηp2 = 0.01). No significant differences were observed for the other neurodevelopmental outcomes. In mixed models adjusted for the same covariates that aimed to examine change in outcomes over time, prenatal SARS-CoV-2 infection exposure was not associated with developmental change in any neurodevelopmental outcomes between ages 6 and 24 months.

Conclusions And Relevance: In this longitudinal cohort study of multiple aspects of child neurodevelopment between ages 6 and 24 months, negligible associations between prenatal exposure to SARS-CoV-2 infection and child outcomes were observed. Follow-up research is warranted to determine whether these predominantly null effects persist into later childhood.