UCLA

Abstract  

Importance: Vaccination during pregnancy protects both the pregnant individual and the fetus from severe infectious diseases. Maternal immunization has expanded over the past decade, with new vaccines, robust safety data, and clear evidence of neonatal benefit through transplacental IgG transfer. 

Objective: To summarize current evidence regarding the safety, efficacy, and clinical recommendations for vaccines administered before and during pregnancy, outline strategies to address vaccine hesitancy, and provide an updated reference of vaccines recommended and contraindicated during pregnancy. 

Evidence Acquisition: Evidence synthesized from guidelines issued by the CDC, ACOG, SMFM, and major peer-reviewed publications including randomized trials, observational studies, vaccine safety surveillance systems, and meta-analyses. Literature informing disease burden, immune physiology, and perinatal outcomes associated with vaccine-preventable diseases also reviewed. 

Results: Influenza, Tdap, and COVID-19 vaccines demonstrate strong maternal and neonatal protective effects with excellent safety profiles. The RSV vaccine offers additional infant protection against severe lower respiratory tract disease. Several other vaccines (e.g., hepatitis A and B, meningococcal, polio, rabies) can be administered in pregnancy when clinically indicated. Live-attenuated vaccines remain contraindicated. Maternal immunization is most effective when integrated into routine prenatal care with onsite availability. Vaccine hesitancy can be mitigated through evidence-based counseling, addressing safety concerns, and improving the provider-patient trust relationship. 

Conclusion: Maternal immunization is safe, effective, and essential for preventing morbidity and mortality among pregnant individuals and infants. 

Relevance: This review provides clinicians with an updated guide for counseling, administering, and optimizing vaccine use before, during, and after pregnancy.