Prenatal COVID-19 infection, vaccination: Early child developmental concerns allayed

Neither SARS-CoV-2 infection exposure nor COVID-19 vaccination during pregnancy poses a significant risk to early child development, as shown in a population-level study said to be the largest to date.

In a cohort of nearly 25,000 child–mother pairs, maternal SARS-CoV-2 infection during pregnancy was not associated with any types of developmental concerns in offspring at age 13–15 months, namely overall development (adjusted odds ratio [aOR], 1.16, 95 percent CI, 0.78–1.71), speech-language communication (aOR, 0.83, 95 percent CI, 0.65–1.06), problem solving (aOR, 0.92, 95 percent CI, 0.69–1.23), gross motor (aOR, 0.86, 96 percent CI, 0·69–1·06), personal–social (aOR, 0.79, 95 percent CI, 0.56–1.11), and emotional–behavioural (aOR, 0.97, 95 percent CI, 0.63–1.49). [Lancet Child Adolesc Health 2025;9:162-171]

The findings held true regardless of the trimester in which the infection occurred, except for one, which the investigators described as “anomalous,” wherein first trimester infections were associated with reduced odds of gross motor developmental concerns (aOR, 0.49, 95 percent CI, 0.29–0.82).

With regard to COVID-19 vaccinations during pregnancy, the data showed no link to any early developmental concerns. Vaccinations during the third trimester—when the majority of vaccinated mothers received their shots—were even associated with reduced odds of problem solving (aOR, 0.72, 95 percent CI, 0.57–0.90), personal–social (aOR, 0.73, 95 percent CI, 0.57–0.93), and emotional–behavioural (aOR, 0.58, 95 percent CI, 0.40–0.84) issues in children. The investigators acknowledged that these protective associations were likely due to unmeasured confounding.

“There could be unmeasured factors such as levels of social support, which could be associated with both likelihood of maternal vaccination and child developmental concerns. Or, perhaps more likely, it might be the case that mothers receiving vaccines have greater access to medical advice, or exhibit more proactive health-seeking behaviours, which could also be associated with their child’s developmental concerns,” they continued.

Overall, “our study provides reassuring evidence … on associations between SARS-CoV-2 infections during pregnancy, COVID-19 vaccinations during pregnancy, and risk of developmental concerns at age 13–15 months,” the investigators said.

Previous studies on SARS-CoV-2 infections during pregnancy and later child developmental outcomes have yielded inconsistent findings, despite similar methodologies. The present data contribute to this ongoing investigation, according to the investigators. [Early Hum Dev 2024;188:105918; JAMA Netw Open 2023;6:e237396; Eur J Pediatr 2023;182:2041-2055; Int J Infect Dis 2024;139:146-152; EClinicalMedicine 2024;72:102628]

The observations regarding vaccine safety are of particular importance, especially when viewed in light of existing research demonstrating COVID-19 vaccination’s protective effect against adverse maternal and foetal outcomes, they added. [Lancet Digit Health 2023;5:e594-e606]

Nevertheless, “the findings should be interpreted with caution, as developmental concerns often do not become apparent until children are older and there are more demands placed on them… Therefore, developmental outcomes among those born during the COVID-19 pandemic should continue to be monitored,” they said.

For the study, the investigators used population-level linked administrative health dataset involving 24,919 children (51.2 percent boys, 89.6 percent White) born during the COVID-19 pandemic in Scotland and their mothers. Of these, 631 children (6.5 percent) were born to mothers exposed to SARS-CoV-2 at some point during pregnancy, with 427 (1.7 percent) exposed in first trimester, 541 (2.2 percent) in second trimester, and 672 (2.7 percent) in third trimester.

A total of 4,943 (19.8 percent) children were born to mothers who were vaccinated against COVID-19 during pregnancy, of which 1,395 (5.6 percent) mothers received the vaccine in second trimester and 4,369 (17.5 percent) in third trimester.