The impact of the COVID-19 pandemic on infant obesity: A nationwide retrospective cohort study.

BACKGROUND: Lifestyle changes, such as those related to the COVID-19 pandemic, including alterations in physical activity and dietary habits, are known to affect pregnancy outcomes. In particular, suboptimal intrauterine conditions during pregnancy are known to influence not only fetal growth but also growth during infancy. However, research on the impact of the environmental changes caused by the COVID-19 pandemic on the growth of infants and children during their early years is lacking. To address this issue, this study evaluated the effect of the COVID-19 pandemic on obesity in infants.

METHODS: This retrospective cohort study used the data collected from the Korea National Health Insurance (KNHI) claims database. The data of 1985,678 women who delivered infants between 2015 and 2021 were collected. Women who delivered during the pandemic and those who delivered during the pre-pandemic period were matched in a 1:1 frequency-matched pair procedure for factors such as age, hypertension, diabetes mellitus, preeclampsia, gestational diabetes mellitus, mode of delivery, gestational age at delivery, offspring sex, and birth weight. Finally, 197,580 women were enrolled. The weight and head circumference of infants (4-6 months of age) of the COVID-19 pandemic group were compared with those of the pre-pandemic group.

RESULTS: The COVID-19 pandemic group infants exhibited significantly higher weight and prevalence of obesity at 4-6 months of age compared to infants in the pre-pandemic group. After adjustment for covariates, pandemic group infants had a higher risk of obesity (odds ratio: 1.54, 95% confidence interval: 1.51-1.57) compared to the pre-pandemic group infants.

CONCLUSION: The COVID-19 pandemic has had a notable impact on the weight of infants aged 4-6 months. This suggests that pandemic conditions may influence the growth of newborns, underscoring the importance of monitoring and assessing trends in the growth of infants born during such crises.