| Tdap timing | 27–36 weeks gestation (each pregnancy) (CDC/ACOG recommendation) |
| Flu vaccine timing | Any trimester during flu season (CDC Advisory Committee on Immunization Practices) |
| COVID-19 vaccine | Recommended before and during pregnancy (CDC and ACOG guidance) |
| Live vaccines to avoid | MMR, varicella — defer until postpartum (CDC immunization schedule) |
| RSV vaccine availability | Approved for use at 32–36 weeks (seasonal) (FDA-approved; consult your provider) |
| Protective benefit to newborn | Maternal antibodies cross the placenta (Established immunological mechanism) |
Why Vaccination Matters During Pregnancy
Pregnancy creates a unique opportunity to protect two people at once. When an expectant mother receives certain vaccines, her immune system produces antibodies that can cross the placenta, giving the newborn a head start on protection against diseases before they are old enough to receive their own immunizations.
This approach is especially important for pertussis (whooping cough) and influenza — two illnesses that can be life-threatening in newborns and young infants. By the time a baby receives their first vaccines at two months of age, several weeks of vulnerability have already passed. Maternal immunization helps bridge that gap.
For a broader picture of immunizations relevant to adult women, see vaccines recommended across a woman's adult life.
| Tdap timing | 27–36 weeks gestation (each pregnancy) (CDC/ACOG recommendation) |
| Flu vaccine timing | Any trimester during flu season (CDC Advisory Committee on Immunization Practices) |
| COVID-19 vaccine | Recommended before and during pregnancy (CDC and ACOG guidance) |
| Live vaccines to avoid | MMR, varicella — defer until postpartum (CDC immunization schedule) |
| RSV vaccine availability | Approved for use at 32–36 weeks (seasonal) (FDA-approved; consult your provider) |
| Protective benefit to newborn | Maternal antibodies cross the placenta (Established immunological mechanism) |
Vaccines Routinely Recommended During Pregnancy
Tdap (tetanus, diphtheria, pertussis): Recommended during every pregnancy, ideally between weeks 27 and 36 of gestation. Timing in the third trimester maximizes the transfer of protective antibodies to the baby. This is one of the most clearly supported prenatal vaccine recommendations from both the CDC and ACOG.
Inactivated influenza vaccine: Recommended during flu season regardless of trimester. Pregnancy increases the risk of severe influenza complications, and the inactivated (not live) formulation is considered safe at any stage. Note that the nasal spray flu vaccine is a live-attenuated formulation and is not recommended during pregnancy.
COVID-19 vaccines: Current CDC and ACOG guidance supports COVID-19 vaccination before and during pregnancy, citing evidence that pregnancy increases risk of severe illness. Specific product availability and timing should be discussed with your provider, as recommendations may evolve.
RSV vaccine: The FDA has approved an RSV vaccine for use between 32 and 36 weeks gestation, administered on a seasonal basis. This is a newer option; your provider can advise whether it is appropriate for your situation.
Always Confirm Your Vaccination Status at Each Prenatal Visit
Vaccine recommendations can be updated as new evidence emerges. Your obstetric or primary care provider will review your immunization history and advise which vaccines are appropriate based on your specific health status, trimester, and any conditions that may affect recommendations. This article provides general educational information only — it is not a substitute for individualized medical guidance.
Vaccines Generally Deferred Until After Delivery
Several vaccines are routinely avoided during pregnancy because they contain live-attenuated viruses. These include:
- MMR (measles, mumps, rubella)
- Varicella (chickenpox)
- Live-attenuated influenza vaccine (nasal spray formulation)
The theoretical concern is that a live virus — even a weakened one — could pose a risk to the developing fetus. If you are not immune to rubella or varicella before pregnancy, your provider will typically recommend vaccination postpartum, before any future pregnancy.
Postpartum vaccination is also part of a broader cocooning strategy — ensuring that all close household contacts are up to date on pertussis, flu, and other vaccines to protect a newborn who cannot yet be vaccinated. Vaccines that families often miss can leave gaps in this protective circle.
How to Approach This With Your Care Team
Vaccine decisions during pregnancy should always be made in partnership with a qualified healthcare provider — typically an OB-GYN, certified nurse-midwife, or primary care physician who has access to your full health history. Factors such as prior vaccination records, underlying conditions, allergies, and gestational age all influence individual recommendations.
Bring a list of any vaccines you received in recent years to your first prenatal appointment. If you are unsure of your immunization history, your provider can check titers (blood tests measuring antibody levels) for certain diseases like rubella and varicella.
Concerns about vaccine safety during pregnancy are common and understandable. Research in this area is ongoing, and the general consensus among major health organizations is that the vaccines routinely recommended during pregnancy have a well-established safety record — but your provider is the right person to address questions specific to your situation. For context on how other medicines are evaluated in pregnancy, understanding general guidance on OTC medicines during pregnancy can be a helpful reference.
This article is for general informational and educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional regarding vaccines and any other health decisions during pregnancy.