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Vaccines During Pregnancy and Breastfeeding

Ideally, women should be immunized before becoming pregnant in order to be protected against infectious diseases, but staying up-to-date with immunizations can be difficult. When health professionals recommend vaccinations during pregnancy, they must weigh the risks versus benefits to both the mother and baby, before and after delivery. These decisions may vary based on vaccine type, vaccine safety profile, and risk of the disease.

Generally, pregnant women are not included in clinical trials carried out by vaccine manufacturers. This limits vaccine safety data available for this group of people. Based on available data from post-marketing studies and vaccine registries, public health officials and healthcare providers make recommendations about which vaccines are beneficial during pregnancy. Several vaccines are recommended for women to take during pregnancy, especially because they may offer the baby passive immunity (antibodies) against disease. Generally during pregnancy inactivated vaccines are recommended more often than live vaccines. Live vaccines pose a theoretical risk of harm to the fetus, so it is generally recommended that women wait to be vaccinated with live vaccines until after pregnancy. The CDC suggests that inactivated vaccines, when given, generally be delayed until the second trimester. 

Learn more about:

Vaccines Generally Recommended during Pregnancy

  • Influenza (Inactivated)
  • Tdap **
  • Hepatitis B*
  • Pneumococcal*
  • Meningococcal*
  • Rabies*

*These vaccines are not routinely recommended during pregnancy, but may be recommended for women at increased risk for infection such as during travel, working in a healthcare facility,or due to certain existing chronic conditions

** Tdap is recommended with each pregnancy. To maximize the maternal antibody response and passive antibody transfer to the infant, optimal timing for Tdap administration is between 27 and 36 weeks of gestation although Tdap may be given at any time during pregnancy. 

Vaccines Generally NOT Recommended during Pregnancy

  • MMR
  • Varicella
  • Smallpox
  • Typhoid vaccine (oral)
  • Live attenuated influenza
  • Yellow Fever
  • Anthrax*
  • HPV**

*Anthrax is not a live vaccine, but it is not recommended during pregnancy- See more information below

**HPV is not a live vaccine but is a newer vaccine and its safety during pregnancy is still being studied. 

Information on Specific Vaccines during Pregnancy

Influenza Vaccination

Pregnant women are more likely than the general population to become severely ill and are at a higher risk for serious complications from influenza illness. Because of this, pregnant women are a priority group for influenza vaccination. Despite current guidance from the Advisory Committee on Immunization Practices to get vaccinated, many pregnant women struggle with making the decision to vaccinate.

Pregnancy vaccines

Why is Influenza Vaccination Recommended for Pregnant Women?1

  • Epidemiologic evidence has shown that vaccination is an effective method for preventing severe influenza illness.
  • The safety profile of inactivated influenza vaccination for use by pregnant women has been demonstrated in various research studies.
  • Pregnant women who get the influenza vaccination may provide antibody protection to their newborn infants.

1. Reference: Tamma PD, Ault KA, del Rio C, Steinhoff MC, Halsey NA, Omer SB. Safety of influenza vaccination during pregnancy. Am J Obstet Gynecol. 2009 Dec;201(6):547-52. Epub 2009 Oct 21. 

Vaccine Safety

Pregnant women often have concerns about the safety of vaccines for themselves and their baby. When recommending any vaccine the benefits of the vaccine are weighed against the risks of the disease, as well as possible vaccine side effects. The United States Food and Drug Administration (FDA) introduced a set of guidelines that establish safety profiles, defining risks for fetal harm caused by vaccinations and other medications used in the United States. The FDA safety category information is available for each vaccine and is included within all package inserts.

FDA Medicine Categories

Pregnancy Category Definition
 A In human studies, pregnant women used the medicine and their babies did not have any problems related to using the medicine.
 B In humans, there are no good studies. But in animal studies, pregnant animals received the medicine, and the babies did not show any problems related to the medicine.


In animal studies, pregnant animals received the medicine, and some babies had problems. But in human studies, pregnant women used the medicine and their babies did not have any problems related to using the medicine.
 C In humans, there are no good studies. In animals, pregnant animals treated with the medicine had some babies with problems. However, sometimes the medicine may still help the human mothers and babies more than it might harm.


No animal studies have been done, and there are no good studies in pregnant women.
 D Studies in humans and other reports show that when pregnant women use the medicine, some babies are born with problems related to the medicine. However, in some serious situations, the medicine may still help the mother and the baby more than it might harm.
 X Studies or reports in humans or animals show that mothers using the medicine during pregnancy may have babies with problems related to the medicine. There are no situations where the medicine can help the mother or baby enough to make the risk of problems worth it. These medicines should never be used by pregnant women.
Table Reference: Pregnancy and Medications,

Information about Inadvertent Vaccination

Sometimes a woman is vaccinated inadvertently while she is pregnant. In these circumstances, we encourage pregnant women to contact the Worldwide DHA Immunization Healthcare Support Center. The IHD Clinical Services can help address questions and provide information, including current research findings and recommendations. IHD Clinical Services staff can also provide contact information for Pregnancy Registries available through vaccine manufacturers.

If an active duty pregnant woman is vaccinated with smallpox vaccine, she should contact the DoD Pregnancy Registry at:

DoD Center for Deployment Health Research 
National Smallpox Vaccine in Pregnancy Registry 
(619) 553-9255   DSN 553-9255   Email

IHD also offers 24/7 vaccine-related clinical consultation at (877) GETVACC (438-8222), Option 1 (DSN 761-4245)

Information about Breastfeeding and Vaccines

Breastfeeding mothers should be vaccinated according to routine and recommended schedules except for smallpox and yellow fever vaccination.

  • Smallpox vaccine is contraindicated for use in breastfeeding mothers. This is because live vaccinia virus can be inadvertently transmitted from a lactating mother to her infant through close contact transmission.
  • Yellow Fever vaccination for breastfeeding mothers should be avoided if possible, due to the possible risk for the transmission of 17D virus to the breastfeeding child. Get the latest information related to international travel and breastfeeding.

Articles of Interest

  • MCN Am J Matern Child Nurs. 2009 Mar-Apr;34(2):98-105. Administration of vaccinations in pregnancy and postpartum. Bruhn K, Tillett J. Aurora UW Midwifery and Wellness Center, Aurora Sinai Medical Center, Milwaukee, USA. Comment in: MCN Am J Matern Child Nurs. 2009 Jul-Aug;34(4):255; author reply 255. 
  • Ryan MA, Gumbs GR, Conlin AM, Sevick CJ, et al. Evaluation of preterm births and birth defects in liveborne infants of US military women who received smallpox vaccine. Birth Defects Res A Clin Mol Teratol. 2009;82(7):533-9.
  • Ryan MA, Seward JF; Smallpox Vaccine in Pregnancy Registry Team. Pregnancy, birth, and infant health outcomes from the National Smallpox Vaccine in Pregnancy Registry, 2003-2006. Clin Infect Dis. 2008;46 Suppl 3:S221-6.
  • Napolitano PG, Ryan MA, Grabenstein JD. Pregnancy discovered after smallpox vaccination: Is vaccinia immune globulin appropriate? Am J Obstet Gynecol. 2004;191(6):1863-7. 

Last Updated: March 25, 2024
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