Jihong Liu, ScD, highlights adverse perinatal outcomes linked to the COVID pandemic

In a recent video with Contemporary OB/GYN, Jihong Liu, ScD, from the University of South Carolina, discussed how COVID-19 infection and pandemic-related stressors have impacted pregnancy and perinatal outcomes, based on a study conducted using statewide birth records from South Carolina between January 2018 and December 2021.

Liu explained that systematic reviews have consistently shown an association between COVID-19 infection during pregnancy and heightened risks of adverse outcomes. These include preterm birth, low birth weight, stillbirth, neonatal intensive care unit (NICU) admissions, and preeclampsia. The severity of COVID-19 further increases these risks. However, Liu noted that much of the existing research focuses narrowly on infection and often fails to account for broader pandemic-related factors such as unemployment, income instability, and limited health care access—all of which may independently affect pregnancy outcomes.

To address this gap, Liu’s team categorized pregnant women into 3 exposure groups: pre-pandemic (those who conceived and delivered before March 1, 2020), partially exposed (those who conceived before but delivered during the pandemic), and fully exposed (those who both conceived and delivered during the pandemic). Women in the partially exposed group, especially during the early months of the pandemic, had a lower risk of preterm birth and low birth weight compared to the pre-pandemic group. However, those in the fully exposed group experienced significantly higher rates of preterm birth, low birth weight, NICU admissions, and decreased breastfeeding initiation.

The study also confirmed that COVID-19 infection during pregnancy, particularly in moderate to severe cases, increased the likelihood of preterm birth and NICU admission. Infections in the third trimester were particularly risky, raising the chances of low birth weight and early delivery. Notably, SARS-CoV-2 infection itself did not affect all pregnancy outcomes, suggesting a nuanced interplay between infection severity and timing.

Liu emphasized the importance of considering both direct infections and indirect pandemic stressors when addressing maternal and neonatal health. She concluded that public health strategies should account for these dual influences, both infection control and mitigating pandemic-related disruptions, to optimize pregnancy outcomes.

This video is part 1 of a 2-part series. Check back tomorrow for part 2.

References

Sevoyan M, Liu J, Shih Y, Hung P, Zhang J, Li X. Associations of pregnancy timing relative to the COVID-19 pandemic, maternal SARS-CoV-2 infection, and adverse perinatal outcomes. Annals of Epidemiology. 2025;102:94-101. doi:10.1016/j.annepidem.2025.01.006