What vaccines are contraindicated (not recommended) in pregnancy?

Vaccines Contraindicated During Pregnancy

Live attenuated vaccines are contraindicated during pregnancy due to theoretical risk of placental transmission to the fetus. 1, 2

Specific Contraindicated Vaccines

• Measles, Mumps, Rubella (MMR) vaccine is contraindicated during pregnancy due to theoretical risk to the developing fetus 1, 2
• Varicella (chickenpox) vaccine should not be administered during pregnancy 1, 2
• Smallpox (vaccinia) vaccine is contraindicated and is the only vaccine known to cause harm to a fetus when administered to a pregnant woman 1
• Live attenuated influenza vaccine (nasal spray) should not be used during pregnancy 2
• Live attenuated oral polio vaccine is contraindicated, although the inactivated polio vaccine is considered safe 1
• Live attenuated cholera vaccine is contraindicated, while the inactivated oral vaccine can be considered in high-risk situations 1
• Live attenuated hepatitis A vaccine should not be used, though the inactivated version can be administered when necessary 1
• Live attenuated Japanese encephalitis vaccine is contraindicated, while the inactivated version may be considered for travel to endemic areas 1

Safe Vaccines During Pregnancy

• Inactivated influenza vaccine is recommended during any trimester of pregnancy 1, 2
• Tdap (Tetanus, diphtheria, acellular pertussis) is recommended between 27-36 weeks of gestation in every pregnancy 2, 3
• Hepatitis B vaccine is recommended for pregnant women at risk for hepatitis B virus infection 1, 2
• Inactivated polio vaccine (IPV) can be administered to pregnant women at risk for exposure 1
• Pneumococcal vaccines can be used if protection of the woman is considered necessary 1
• Meningococcal vaccines should be considered for women at increased risk 1
• Rabies vaccine should not be withheld in post-exposure situations, as the disease is nearly 100% fatal 1, 4

Important Clinical Considerations

• Women who inadvertently receive live vaccines during pregnancy should not be counseled to terminate pregnancy, as the risk is largely theoretical 5
• Non-pregnant women who receive live vaccines should delay pregnancy for at least 4 weeks 5
• For pregnant women who must travel to areas where yellow fever is endemic, yellow fever vaccine should be administered as the risk of infection outweighs the theoretical risk of vaccination 1
• Inactivated vaccines, bacterial vaccines, and toxoids have shown no evidence of adverse fetal effects 3, 6

Decision-Making Algorithm for Vaccination During Pregnancy

1. Is the vaccine live or inactivated?

   • If live attenuated: Contraindicated unless risk of disease significantly outweighs theoretical risks 1, 2
   • If inactivated: Generally considered safe 1, 3

2. Is the vaccine routinely recommended during pregnancy?

   • Tdap and inactivated influenza vaccines are routinely recommended 2, 7
   • Other inactivated vaccines should be given based on risk assessment 1

3. Is there a significant exposure risk?

   • For high-risk exposures (e.g., rabies), vaccination should proceed regardless of vaccine type 1, 4
   • For travel to endemic areas, risk-benefit assessment should guide decisions 1

Common Pitfalls to Avoid

• Delaying influenza vaccination until a specific trimester - it can be given at any time during pregnancy 2, 7
• Missing the optimal window (27-36 weeks) for Tdap administration 2
• Withholding rabies post-exposure prophylaxis due to pregnancy - this should never be delayed as rabies is almost universally fatal 4
• Failing to recognize that while live vaccines are generally contraindicated, the risk is theoretical for most vaccines except smallpox 1