SOGC Clinical Practice GuidelineNo. 357-Immunization in Pregnancy
Introduction
Immunization programs are among the most cost-beneficial health interventions. Women interact with the health care system regularly during the preconception period and during pregnancy; therefore, obstetrical care providers are well-placed to review their immunization status and recommend vaccinations. This can significantly reduce the occurrence of preventable diseases, benefiting not only the woman and her infant but also the rest of the population.
The overall objective of vaccination in pregnancy is to induce a state of immunity such that the woman and the fetus are protected following exposure to the organism for which the immunization is given. In addition, this offers an opportunity for protection of the neonate for the first few months of life.
Vaccines may be prepared from various sources, including the inactivated agent, live-attenuated agent and modified and single antigen recombinant forms of the organism. Active immunization relies on the administration of antigens and results in a prompt but transient IgM response in the host. This is followed by a rise in IgG antibody production that will be more or less sustained. In cases in which the response is not sustained, booster doses may be required for long-term immune memory. Of note, oral vaccines will stimulate IgA initially as opposed to IgM (parenteral).
This document reviews indications for and contraindications to immunization during pregnancy and makes recommendations for the use of specific vaccines during pregnancy, acknowledging that immunization schedules in Canada vary according to province and territory, despite calls for harmonization1, 2 (Table 2).
Section snippets
Importance of the Prenatal Care Provider as an Immunization Advocate
Prenatal care providers should obtain a thorough immunization history. In many cases, women present for prenatal care without having had their immunization status reviewed since they completed the school-age vaccination schedule. Digital tools like CANimmunize (digital immunization record for all Canadians to securely track, store, and update immunization records on a smartphone) can facilitate this review.
Prenatal care provides a unique window of opportunity to offer specific killed or
Live and Live-Attenuated Vaccines
In general, live and/or live-attenuated virus vaccines are contraindicated during pregnancy because there is a theoretical risk of infection to the fetus. To date, however, there is no evidence to demonstrate a teratogenic risk from any currently available live product (e.g., MMR, varicella).7, 8 Hence, inadvertent vaccination should not be an indication for termination of pregnancy. With the exception of the yellow fever vaccine, these products are safe and acceptable for breastfeeding mothers.
Hepatitis B Vaccine
Acute maternal hepatitis B infection during pregnancy poses a high risk of mother-to-child transmission (up to 60% in the third trimester). These infants have a 70% to 90% risk of chronic hepatitis B infection. Pregnant women at high risk for acquiring hepatitis B infection during pregnancy (e.g., more than 1 sex partner during the previous 6 months, been evaluated or treated for a sexually transmitted disease, recent or current injection drug use, having had a hepatitis B-infected sex partner,
Side Effects of Vaccines and Contraindications
Vaccines may cause various side effects, which should not all be interpreted as contraindications. Side effects can be divided in the following 5 categories: (1) immediate/early, (2) local, (3) systemic, (4) allergic, and (5) long term.
- 1.
Immediate/early effects include fainting and vasovagal reactions. These are differentiated from anaphylactic shock (see in the following list). Patients who have received a vaccine should be kept in the waiting room for observation for 15 to 30 minutes.
- 2.
Local
Conclusion
The development of new vaccines and the accumulating information about vaccine safety ensure that health care providers can provide immunizations and/or advice about immunization for their pregnant patients. This is most important in disease prevention, and antenatal care providers must play an active role in vaccine counselling and administration. Furthermore, it is imperative that more research efforts be focused in the area of immunization in pregnancy.
Acknowledgements
The authors and Infectious Diseases Committee wish to thank Dr. Andrée Gruslin, Dr. Marc Steben, Dr. Scott Halperin, and Dr. Deborah Money for their input and contributions to the original version of the guideline.
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Cited by (15)
Pertussis Non-Vaccination During Pregnancy Despite Advice From Prenatal Care Providers
2023, Journal of Obstetrics and Gynaecology CanadaPerformance evaluation of the bio-rad BioPlex 2200 multiplex system in the detection of measles, mumps, rubella, and varicella-zoster antibodies
2023, Journal of Clinical Virology PlusCitation Excerpt :According to the 2017 Childhood National Immunization Coverage Survey (cNICS), over 90% of Canadian 2-year-olds are vaccinated against MMR and 83% are vaccinated against varicella[2]. Despite this progress, several populations remain at risk for MMRV infection including healthcare workers (HCW), pregnant women, and individuals who are immunocompromised[3,4]. Additionally, declining immunization rates, vaccine failures, and waning immunity are contributing to the risk of viral outbreak[5,6].
Pertussis Vaccination in Canadian Pregnant Women, 2018–2019
2022, Journal of Obstetrics and Gynaecology CanadaCitation Excerpt :For these reasons, the National Advisory Committee on Immunization recommended in February 2018 that Tdap be administered in every pregnancy in Canada, ideally between 27 and 32 weeks of gestation.9 In March 2018, the Society of Obstetricians and Gynaecologists of Canada issued a new clinical practice guideline on immunization in pregnancy that included a recommendation that every pregnant woman be offered Tdap, ideally between 21 and 32 weeks.10 As of November 2019, all provinces and territories except for Ontario and British Columbia had implemented programs to provide pertussis vaccination free of charge to pregnant women.
Immunization in Pregnancy: The Future for Neonatal Protection
2018, Journal of Obstetrics and Gynaecology CanadaL'immunisation pendant la grossesse : l'avenir de la protection néonatale
2018, Journal of Obstetrics and Gynaecology CanadaVaccination during pregnancy: A golden opportunity to embrace
2023, International Journal of Gynecology and Obstetrics
This document reflects emerging clinical and scientific advances on the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed. Local institutions can dictate amendments to these opinions. They should be well-documented if modified at the local level. None of these contents may be reproduced in any form without prior written permission of the publisher.
Women have the right and responsibility to make informed decisions about their care in partnership with their health care providers. To facilitate informed choice, women should be provided with information and support that is evidence based, culturally appropriate, and tailored to their needs. The values, beliefs, and individual needs of each woman and her family should be sought, and the final decision about the care and treatment options chosen by the woman should be respected.