Guidelines for Vaccinating Pregnant Persons

Routine Vaccines

COVID-19

• COVID-19 vaccination is recommended for persons who are pregnant, might become pregnant, were recently pregnant or are breastfeeding. The safety and effectiveness of COVID-19 vaccination indicates that the benefits of vaccination outweigh any known or potential risks of COVID-19 vaccination during pregnancy.

Dengue

• Pregnancy is a precaution for Dengvaxia. Vaccination should generally be deferred but might be indicated if the benefit of protection from the vaccine outweighs the risk for an adverse reaction. 1
• Pregnant females, who are at increased risk for dengue-related complications, were not specifically studied in the Dengvaxia trial. The limited number of pregnant females inadvertently vaccinated during the trial had a similar frequency of adverse pregnancy outcomes (e.g., spontaneous abortion, intrauterine death, and stillbirth) as occurred in the control group; however, the number of vaccinated pregnant females was not sufficient to determine a possible effect of Dengvaxia on pregnancy. 1

Hepatitis A

• Pregnant women should be vaccinated with HepA vaccine if they are identified to be at risk for HAV infection during pregnancy (e.g., international travelers, persons who use injection or noninjection drugs [i.e., all those who use illegal drugs], persons who have occupational risk for infection, persons who anticipate close personal contact with an international adoptee, or persons experiencing homelessness) or for having a severe outcome from HAV infection (e.g., persons with chronic liver disease or persons with HIV infection)
• The safety of hepatitis A vaccination during pregnancy has not been determined; however, because hepatitis A vaccine (HepA) is produced from inactivated HAV, the theoretic risk to the developing fetus is expected to be low. The risk associated with vaccination should be weighed against the risk for hepatitis A in pregnant women who might be at high risk for exposure to HAV. 2
• Pregnant women should be vaccinated with HepA vaccine if they are at risk for infection or severe outcome from infection during pregnancy.

Hepatitis B

• Pregnancy is not a contraindication to vaccination. Limited data suggest that developing fetuses are not at risk for adverse events when hepatitis B vaccine is administered to pregnant women. Available vaccines contain noninfectious HBsAg and should cause no risk of infection to the fetus. 3
• If not already vaccinated with hepatitis B vaccine (HepB), pregnant women should be vaccinated with HepB in pregnancy, since all adults 19 through 59 years of age are recommended to receive HepB vaccination.
  • Note: Heplisav-B and PreHevbrio are not recommended in pregnancy due to lack of safety data in pregnant women. Therefore, providers should continue to use Engerix-B, Recombivax HB, or Twinrix for individuals needing hepatitis B vaccination during pregnancy. 4

Human Papillomavirus (HPV)

• HPV vaccines are not recommended for use in pregnant women. If a woman is found to be pregnant after initiating the vaccination series, the remainder of the 3-dose series should be delayed until completion of pregnancy. Pregnancy testing is not needed before vaccination. If a vaccine dose has been inadvertently administered during pregnancy, no intervention is needed. 5
• A pregnancy registry has been established for 9vHPV. Pregnancy registries for 4vHPV and 2vHPV have been closed with concurrence from FDA. 6

Influenza (Inactivated or Recombinant)

• Pregnant and postpartum women are at higher risk for severe illness and complications from influenza than women who are not pregnant because of changes in the immune system, heart, and lungs during pregnancy…. Influenza vaccination can be administered at any time during pregnancy, before and during the influenza season. Women who are or will be pregnant during influenza season should receive inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV). 7

Influenza (LAIV)

• · Live attenuated influenza vaccine (LAIV) is https://www.cdc.gov/mmwr/volumes/72/rr/rr7202a1.htm HYPERLINK "bookmark://R7" 7

Mpox

• Available human data on JYNNEOS administered to pregnant women are insufficient to determine vaccine-associated risks in pregnancy. However, animal models, including rats and rabbits, have shown no evidence of harm to a developing fetus. 8
• Vaccine recipients might consider avoiding high-risk exposures until after temporary conditions (e.g., pregnancy or transient therapy with immunocompromising therapeutics) are completed. If high-risk exposures cannot be avoided, persons who are pregnant, immunocompromised, or breastfeeding or who have atopic dermatitis may receive JYNNEOS in consultation with their health care provider and after careful consideration of the risks and benefits. 8

Measles, Mumps, Rubella (MMR)

• MMR vaccines should not be administered to women known to be pregnant or attempting to become pregnant. Because of the theoretical risk to the fetus when the mother receives a live virus vaccine, women should be counseled to avoid becoming pregnant for 28 days after receipt of MMR vaccine. If the vaccine is inadvertently administered to a pregnant woman or a pregnancy occurs within 28 days of vaccination, she should be counseled about the theoretical risk to the fetus. 9
• Routine pregnancy testing of women of childbearing age before administering a live-virus vaccine is not recommended. MMR or varicella vaccination during pregnancy should not be considered a reason to terminate pregnancy. 10
• Rubella-susceptible women who are not vaccinated because they state they are or may be pregnant should be counseled about the potential risk for CRS and the importance of being vaccinated as soon as they are no longer pregnant. 11

Meningococcal (MenACWY or MPSV4)

• Pregnancy should not preclude vaccination with MenACWY, if indicated. Women of childbearing age who become aware that they were pregnant at the time of MenACWY vaccination should contact their health-care provider or the vaccine manufacturer so that their experience might be captured in the vaccine manufacturer’s registry of vaccination during pregnancy. 12

Meningococcal (MenB)

• No randomized controlled clinical trials have been conducted to evaluate use of MenB vaccines in pregnant or lactating women. Vaccination should be deferred in pregnant and lactating women unless the woman is at increased risk, and, after consultation with her health care provider, the benefits of vaccination are considered to outweigh the potential risks. 12

Pneumococcal Conjugate (PCV)

• ACIP has not published pregnancy recommendations for any PCV product at this time. 13

Pneumococcal Polysaccharide (PPSV23)

• The safety of pneumococcal polysaccharide vaccine during the first trimester of pregnancy has not been evaluated, although no adverse consequences have been reported among newborns whose mothers were inadvertently vaccinated during pregnancy. 13

Polio (IPV)

• Although no adverse effects of IPV have been documented among pregnant women or their fetuses, vaccination of pregnant women should be avoided on theoretical grounds. However, if a pregnant woman is at increased risk for infection and requires immediate protection against polio, IPV can be administered in accordance with the recommended schedules for adults. 14

Respiratory Syncytial Virus (RSV)

• On September 22, 2023, ACIP and CDC recommended maternal Pfizer RSVpreF (Abrysvo) vaccination in pregnant persons as a one-time dose at 32 weeks and zero days’–36 weeks and 6 days’ gestation using seasonal administration (meaning September–January in most of the continental United States) for prevention of RSV-associated LRTI in infants aged <6 months. 15
  • Note: Only Pfizer RSVpreF (Abrysvo) may be administered to pregnant persons; Arexvy (GSK) and mRESVIA (Moderna) vaccines should not be administered during pregnancy. 15

• Administering maternal RSVpreF vaccine starting in September (1–2 months before the anticipated start of the RSV season) and continuing through January (2–3 months before the anticipated end of the RSV season) will maximize cost-effectiveness and benefits. In jurisdictions with RSV seasonality that differs from most of the continental United States, including Alaska, southern Florida, Guam, Hawaii, Puerto Rico, U.S.-affiliated Pacific Islands, and U.S. Virgin Islands, providers should follow state, local, or territorial guidance on timing of maternal RSVpreF vaccination. 15

Tetanus, Diphtheria, and Pertussis (Tdap); Tetanus and Diphtheria (Td)

• Health-care personnel should administer a dose of Tdap during each pregnancy irrespective of the patient’s prior history of receiving Tdap. 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. 16
• Currently available data suggest that vaccinating earlier in the 27 through 36–week period will maximize passive antibody transfer to the infant. 16
• For women not previously vaccinated with Tdap, if Tdap is not administered during pregnancy, Tdap should be administered immediately postpartum. 16
• Available data from studies do not suggest any elevated frequency or unusual patterns of adverse events in pregnant women who received Tdap and that the few serious adverse events reported were unlikely to have been caused by the vaccine. 17
• Wound Management: If a Td booster is indicated for a pregnant woman, health-care providers should administer Tdap.
• Unknown or Incomplete Tetanus Vaccination: To ensure protection against maternal and neonatal tetanus, pregnant women who never have been vaccinated against tetanus should receive three vaccinations containing tetanus and reduced diphtheria toxoids. The recommended schedule is 0, 4 weeks and 6 through 12 months. Tdap should replace 1 dose of Td, preferably between 27 and 36 weeks’ gestation. 16
• Providers are encouraged to report administration of Tdap to a pregnant woman, regardless of trimester, to the appropriate manufacturer’s pregnancy registry: for Adacel® to Sanofi Pasteur, telephone 1-800-822-2463 and for Boostrix® to GlaxoSmithKline Biologicals, telephone 1-888-452-9622. 17

Varicella

• Because the effects of the varicella virus on the fetus are unknown, pregnant women should not be vaccinated. Nonpregnant women who are vaccinated should avoid becoming pregnant for 1 month after each injection. For persons without evidence of immunity, having a pregnant household member is not a contraindication for vaccination. 18
• Wild-type varicella poses a low risk to the fetus. Because the virulence of the attenuated virus used in the vaccine is less than that of the wild-type virus, the risk to the fetus, if any, should be even lower. 18
• Routine pregnancy testing of women of childbearing age before administering a live-virus vaccine is not recommended. If a pregnant woman is inadvertently vaccinated or becomes pregnant within 4 weeks after MMR or varicella vaccination, she should be counseled about the theoretical basis of concern for the fetus; however, MMR or varicella vaccination during pregnancy should not be considered a reason to terminate pregnancy. 10
• To monitor the pregnancy outcomes of women inadvertently vaccinated with VZV-containing vaccines immediately before or during pregnancy, Merck and CDC established the Merck/CDC Pregnancy Registry for VZV-Containing Vaccines in 1995. The low rate of exposure of varicella-susceptible women of childbearing age to VZV-containing vaccines, in addition to the rarity of the outcome, contribute to the low feasibility that the registry will provide more robust data on the risk for congenital varicella syndrome within a reasonable timeframe. New patient enrollment was discontinued as of October 16, 2013. Merck will continue to monitor pregnancy outcomes after inadvertent exposures to VZV-containing vaccines during pregnancy or within 3 months before conception. CDC and the Food and Drug Administration will continue to monitor adverse events after vaccination with VZV-containing vaccines through the Vaccine Adverse Event Reporting System (VAERS). New cases of exposure immediately before or during pregnancy or other adverse events after vaccination with Varivax and ProQuad should be reported to Merck (telephone, 1-877-888-4231) and to VAERS. 19

Zoster

• There is currently no ACIP recommendation for Shingrix (RZV) use in pregnancy. Consider delaying RZV until after pregnancy. 20

Non-Routine Vaccines

Adenovirus

• Adenovirus Type 4 and Type 7 Vaccine, Live, Oral is contraindicated for use in pregnant women. Avoid becoming pregnant following vaccination for at least 6 weeks after vaccination to prevent the fetus from being exposed to adenovirus. 21
• Adenovirus Type 4 and Type 7 Vaccine, Live, Oral contains live virus that is shed in the stool for up to 28 days following vaccination and can cause disease if transmitted. It is given to individuals, undergoing intensive military training, who have limited contact with pregnant women, children under age seven and persons with compromised immune systems. 21

Anthrax

• In a pre-event setting, in which the risk for exposure to aerosolized B. anthracis spores is presumably low, vaccination of pregnant women is not recommended and should be deferred until after pregnancy. 22
• In a post-event setting that poses a high risk for exposure to aerosolized B. anthracis spores, pregnancy is neither a precaution nor a contraindication to PEP. Pregnant women at risk for inhalation anthrax should receive AVA and 60 days of antimicrobial therapy as described. 22

Cholera

• No data exist on use of the currently licensed CVD 103-HgR during pregnancy or while breastfeeding. Prospective travelers who are pregnant and their clinicians should consider the risks associated with traveling to areas with active cholera transmission. 23

Ebola

• Human data available from clinical trials with Ervebo are insufficient to establish the presence or absence of vaccine-associated risk during pregnancy. The decision regarding whether to vaccinate a pregnant woman should involve consideration of the woman’s risk for exposure to EBOV. 24

Japanese Encephalitis (JE)

• Pregnancy is a precaution for the use of JE-VC. Vaccination with JE vaccine usually should be deferred because of a theoretical risk for the developing fetus. However, pregnant people who must travel to an area in which risk for JE is high should be vaccinated if the benefits outweigh the risks of vaccination to the mother and developing fetus. 25

Rabies

• Because of the potential consequences of inadequately managed rabies exposure, pregnancy is not considered a contraindication to postexposure prophylaxis. Certain studies have indicated no increased incidence of abortion, premature births, or fetal abnormalities associated with rabies vaccination.
• If the risk of exposure to rabies is substantial, pre-exposure prophylaxis also might be indicated during pregnancy. Rabies exposure or the diagnosis of rabies in the mother should not be regarded as reasons to terminate the pregnancy. 26

Tick-borne Encephalitis

• TBE virus infection can pose a risk for severe illness in pregnant persons; thus, the benefits of vaccinating pregnant persons when the likelihood of infection is high likely outweigh the potential risks. 27

Typhoid

• No data have been reported on the use of either typhoid vaccine in pregnant women. In general, live vaccines like Ty21a are contraindicated in pregnancy. Vi polysaccharide vaccine should be given to pregnant women only if clearly needed. 28

Vaccinia (Smallpox)

• Because of the limited risk but severe consequences of fetal infection, smallpox vaccine should not be administered in a pre-event setting to pregnant women or to women who are trying to become pregnant. 29
• If a pregnant woman is inadvertently vaccinated or if she becomes pregnant within 4 weeks after smallpox vaccination, she should be counseled regarding concern for the fetus. Smallpox vaccination during pregnancy should not ordinarily be a reason to terminate pregnancy. CDC has established a pregnancy registry to prospectively follow the outcome of such pregnancies and facilitate the investigation of any adverse pregnancy outcome among pregnant women who were inadvertently vaccinated. For enrollment in the registry, contact CDC at 404-639-8253. 29
• Pregnant women who have had a definite exposure to smallpox virus (i.e., face-to-face, household, or close-proximity contact with a smallpox patient) and are, therefore, at high risk for contracting the disease, should be vaccinated. Smallpox infection among pregnant women has been reported to result in a more severe infection than among nonpregnant women. Therefore, the risks to the mother and fetus from experiencing clinical smallpox substantially outweigh any potential risks regarding vaccination. In addition, vaccinia virus has not been documented to be teratogenic, and the incidence of fetal vaccinia is low. 29
• When the level of exposure risk is undetermined, the decision to vaccinate should be made after assessment by the clinician and the patient of the potential risks versus the benefits of smallpox vaccination. 30

Yellow Fever

• Pregnancy is a precaution for YF vaccine administration, compared with most other live vaccines, which are contraindicated in pregnancy. If travel is unavoidable, and the risks for YFV exposure are felt to outweigh the vaccination risks, a pregnant woman should be vaccinated. If the risks for vaccination are felt to outweigh the risks for YFV exposure, pregnant women should be issued a medical waiver to fulfill health regulations. 31
• Because pregnancy might affect immunologic function, serologic testing to document an immune response to the vaccine should be considered. 31
• Although no specific data are available, a woman should wait 4 weeks after receiving YF vaccine before conceiving. 31

Breastfeeding and Vaccination

Breastfeeding is a contraindication for smallpox vaccination, and yellow fever vaccine should be avoided in breastfeeding women if possible. Other vaccines should not affect the safety of breastfeeding and can be given to breastfeeding women if otherwise indicated. Per ACIP:

• “Neither inactivated nor live-virus vaccines administered to a lactating woman affect the safety of breastfeeding for women or their infants. Although live viruses in vaccines can replicate in vaccine recipients (i.e., the mother), the majority of live viruses in vaccines have been demonstrated not to be excreted in human milk. Varicella vaccine virus has not been found in human milk. Although rubella vaccine virus might be excreted in human milk, the virus usually does not infect the infant. If infection does occur, it is well tolerated because the virus is attenuated. Inactivated, recombinant, subunit, polysaccharide, and conjugate vaccines, as well as toxoids, pose no risk for mothers who are breastfeeding or for their infants.” 8

• “Breastfeeding is a contraindication for smallpox vaccination of the mother because of the theoretical risk for contact transmission from mother to infant. Yellow fever vaccine should be avoided in breastfeeding women. However, when nursing mothers cannot avoid or postpone travel to areas endemic for yellow fever in which risk for acquisition is high, these women should be vaccinated.” 8

FDA Pregnancy Categories

Regulation traditionally required that each product be classified under one of five pregnancy categories (A, B, C, D, and X) on the basis of risk of reproductive and developmental adverse effects or, for certain categories, on the basis of such risk weighted against potential benefits.

As of August 2016, most vaccines have not yet converted from the FDA letter categories, and are rated in manufacturers’ package inserts as follows:

• Pregnancy Category B: Human Papillomavirus, Influenza (Fluarix, FluLaval, Afluria, Flublok, Flucelvax, Fluzone, Fluzone Intradermal, Fluvirin, Fluad, FluMist), Japanese Encephalitis (Ixiaro), Meningococcal (Menveo), Tdap (Boostrix), Meningococcal B.
• Pregnancy Category C: Hepatitis A, Hepatitis B, Influenza (Fluzone High Dose, FluMist), MMR, Meningococcal ACWY (Menactra, Menomune), Pneumococcal (Pneumovax23), Td, Tdap (Adacel), Japanese Encephalitis (JE-VAX), Rabies, Typhoid.
• Pregnancy Category D: Anthrax, Vaccinia.

Vaccines that have converted from the letter categories as of August 2016 are:

• Pneumococcal (Prevnar13) – “Available data on Prevnar 13 administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy.”
• Polio – “Animal reproduction studies have not been conducted with IPOL vaccine. It is also not known whether IPOL vaccine can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. IPOL vaccine should be given to a pregnant woman only if clearly needed.”
• Varicella: Contraindication. Varivax should not be administered to pregnant females since wild-type varicella can sometimes cause congenital varicella infection. Pregnancy should be avoided for three months following vaccination with Varivax.
• Yellow Fever: “It is also not known whether YF-195 VAX can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. 196 YF-VAX should be given to a pregnant woman only if clearly needed.”
• Zoster: There is currently no ACIP recommendation for RZV use in pregnancy. Consider delaying RZV until after pregnancy.