# The Timing of Intrauterine Exposure to Maternal SARS-CoV-2 Infection Impacts Neurodevelopment and Growth Trajectories During the First Year of Life

## TL;DR

Exposure to SARS-CoV-2 during pregnancy affects infant neurodevelopment and growth, with differences based on the trimester of exposure and infant sex.

## Contribution

This study identifies sex-specific and trimester-specific effects of maternal SARS-CoV-2 infection on infant neurodevelopment and growth trajectories.

## Key findings

- Male infants exposed to SARS-CoV-2 in utero had higher rates of neurodevelopmental disorders compared to females.
- Exposure during the second or third trimester was linked to higher neurological diagnosis rates than first-trimester exposure.
- Female infants showed lower weight and head circumference growth trajectories compared to males.

## Abstract

Background: The effect of intrauterine exposure to SARS-CoV-2 infection during pregnancy on neurodevelopment and growth trajectories during the first year of life remains under investigation. Methods: We retrospectively reviewed the electronic medical records of all pregnant women who received care at Mayo Health System and tested positive for SARS-CoV-2 (RT-PCR) from March 2020 through October 2021 and examined the effects of fetal sex and trimester of maternal SARS-CoV-2 infection on the risk of neurodevelopmental disorder diagnosis and growth trajectories of head circumference (HC) and body weight (BW) percentiles over the first year of life using linear mixed models. Results: We observed that a higher percentage of male infants (n = 357), compared to females (n = 344), have neurodevelopmental disorders (10.9% vs. 5.2%, p = 0.008), and infants exposed to maternal SARS-CoV-2 infection in the second (n = 183) or third trimester (n = 358) have a higher prevalence of neurological diagnoses compared to those exposed in the first trimester (n = 160) (1st vs. 2nd vs. 3rd trimester: 0% vs. 0.9% vs. 0.7%, respectively, p = 0.037). In addition, female infants, compared to males, had significantly lower BW (B = −0.04, p < 0.0001) and HC (B = −0.06, p < 0.0001) percentile growth trajectories over the first year of life. Moreover, infants exposed to maternal SARS-CoV-2 infection in the second trimester had a significantly lower BW percentile growth trajectory (B = −0.01, p = 0.006), while infants exposed to maternal SARS-CoV-2 infection in the third trimester had a significantly lower HC percentile growth trajectory (B = −0.02, p = 0.02). Conclusions: In utero exposure to maternal SARS-CoV-2 infection could have long-term effects on growth trajectories, depending on the infant’s sex and timing of exposure.