Immunization in pregnancy

Abstract

Objective: To review the evidence and provide recommendations on immunization in pregnancy.

Outcomes: Outcomes evaluated include effectiveness of immunization, and risks and benefits for mother and fetus.

Evidence: The Medline and Cochrane databases were searched for articles published up to June 2007 on the topic of immunization in pregnancy.

Values: The evidence obtained was reviewed and evaluated by the Infectious Diseases Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) under the leadership of the principal authors, and recommendations were made according to guidelines developed by the Canadian Task Force on Preventive Health Care.

Benefits, harms, and costs: Implementation of the recommendations in this guideline should result in more appropriate immunization of pregnant and breastfeeding women, decreased risk of contraindicated immunization, and better disease prevention. Recommendations 1. All women of childbearing age should be evaluated for the possibility of pregnancy before immunization. (III-A) 2. Health care providers should obtain an immunization history from all women accessing prenatal care. (III-A) 3. In general, live and/or live-attenuated virus vaccines are contraindicated during pregnancy, as there is a, largely theoretical, risk to the fetus. (II-3) 4. Women who have inadvertently received immunization with live or live-attenuated vaccines during pregnancy should not be counselled to terminate the pregnancy because of a teratogenic risk. (II-2) 5. Non-pregnant women immunized with a live or live-attenuated vaccine should be counselled to delay pregnancy for at least four weeks. (III) 6. Inactivated viral vaccines, bacterial vaccines, and toxoids are considered safe in pregnancy. (II-1) 7. Women who are breastfeeding can still be immunized (passive-active immunization, live or killed vaccines). (II-1) 8. Pregnant women should be offered the influenza vaccine when pregnant during the influenza season. (II-1).