Risk of Preterm Birth, Congenital Structural Anomalies and Severe Postpartum Hemorrhage After Receipt of NVX-CoV2373 Vaccine During Pregnancy
Eunseon Gwak, Young June Choe, Ju-Young Shin, Smita Shah, Sarah Sellers, Seung-Ah Choe, Jonathan FixBackground:
Information on maternal and neonatal outcomes following NVX-CoV2373 coronavirus disease 2019 (COVID-19) vaccination in pregnant women is limited.
Methods:
This retrospective cohort study utilized National Health Insurance Service data, linking maternal and neonatal records with COVID-19 vaccination registries in South Korea. Eligible pregnancies included those with recorded births among 20–49-year-old women between February 1 and December 31, 2022, excluding pregnancies with first-trimester severe acute respiratory syndrome coronavirus 2 infections. Pregnant women who received NVX-CoV2373 during pregnancy were matched, 1:4, with COVID-19–unvaccinated women using propensity score methods to account for demographic and clinical variables. Adjusted risk ratios (aRR) and 95% confidence intervals (95% CIs) for preterm birth (PTB), congenital structural anomalies (CSAs) and severe postpartum hemorrhage (sPPH) were estimated using log-binomial regression models. To further characterize NVX-CoV2373 safety, a separate analysis estimated aRRs and 95% CIs comparing women who exclusively received either NVX-CoV2373 or BNT162b2 during pregnancy.
Results:
Among 484 NVX-CoV2373 recipients during pregnancy and their matched sample of 1930 COVID-19–unvaccinated women, there was no observed difference in risk of PTB (aRR = 0.95, 95% CI: 0.75–1.21), CSAs (aRR = 0.57, 0.30–1.09) or sPPH (aRR = 0.65, 0.15–2.90) between groups. Between 476 NVX-CoV2373 and their matched sample of 1497 BNT162b2 recipients during pregnancy, there were no significant differences in risk of PTB (aRR = 1.01, 0.75–1.34), CSAs (aRR = 0.74, 0.42–1.29) or sPPH (aRR = 0.45, 0.10–1.97).
Conclusions:
The risk of PTB, CSAs and sPPH was not statistically different between NVX-CoV2373 and BNT162b2 recipients during pregnancy and COVID-19–unvaccinated women, reinforcing the antepartum safety of NVX-CoV2373 and COVID-19 vaccines in general.