• Pregnant women were excluded from COVID-19 vaccine trials 
  • Newborn outcomes data remains limited 
• Goldshtein et al. (JAMA Pediatrics, 2022) examined whether BNT162b2 mRNA (Pfizer) vaccination during pregnancy is associated with adverse neonatal and early infant outcomes  

• Population-based cohort study 
  • Maccabi Healthcare Services database | 2.5-million-member state-mandated health fund in Israel 
• Population 
  • All singleton live births 
  • Between March and September 2021  
• Exposures 
  • Maternal BNT162b2 mRNA (Pfizer) vaccination during pregnancy 
• Study design 
  • Risk ratios (RR) were calculated for all primary outcomes 
  • Adjustments: Maternal age | Timing of conception | Parity | Socioeconomic status | Population subgroup | Maternal influenza immunization status 
• Primary outcomes 
  • Preterm birth 
  • Small birth weight for gestational age (SGA) 
  • Congenital malformations 
  • All-cause hospitalizations 
  • Infant death 

• 24,288 newborns 
  • 49% female | 96% born at ≥37 weeks gestation 
  • Vaccine exposed in first trimester: 2134 
  • Vaccine exposed in second trimester: 9364 
• No significant differences in any of the primary outcomes between exposed and unexposed newborns 
  • Preterm birth rates  
    • RR 0.95 (95% CI, 0.83 to 1.10) 
  • SGA 
    • RR 0.97 (95% CI, 0.87 to 1.08) 
  • All cause neonatal hospitalizations 
    • RR 0.99 (95% CI, 0.83 to 1.12) 
  • Postneonatal hospitalizations after birth 
    • RR 0.95 (95% CI, 0.84 to 1.07) 
  • Congenital anomalies 
    • RR 0.69 (95% CI, 0.44 to 1.04) 
  • Infant mortality 
    • RR 0.84 (95% CI, 0.43 to 1.72) 

• In this large population-based study, no significant adverse effects of COVID-19 vaccination during pregnancy were found for newborns 
• Limitations include observational design, although an RCT would likely be considered unethical based on all the data suggesting significant benefit during pregnancy  
• The authors state 

Despite limitations, these findings contribute to current evidence in establishing the safety of BNT162b2 to offspring and can be used to inform pregnant patients, couples planning pregnancy, and counseling physicians 

Robust assessments of maternal and offspring safety are important to reduce vaccine hesitancy and increase confidence among pregnant women 

• Prenatal vaccine exposure is likely safe for newborns 

Association of BNT162b2 COVID-19 Vaccination During Pregnancy With Neonatal and Early Infant Outcomes 

Related ObG Topics:

Latest Data on Transplacental Antibody Transfer Following COVID-19 Vaccination

COVID-19 Vaccination Does Not Increase Risk of Preterm Birth or SGA

Vaccines in Pregnant and Lactating Women: Is Immune Response Similar to that of Non-Pregnant Patients?