On October 18, 2001, the Advisory Committee on Immunization Practices (ACIP) reviewed data from several sources indicating that no cases of congenital rubella syndrome (CRS) had been identified among infants born to women who were vaccinated inadvertently against rubella within 3 months or early in pregnancy. On the basis of these data, ACIP shortened its recommended period to avoid pregnancy after receipt of rubella-containing vaccine from 3 months to 28 days.
Data were available from the U.S. Rubella Vaccine in Pregnancy Registry,1 the U.K. National Congenital Rubella Surveillance Programme (National Congenital Registry Surveillance Programme, unpublished data, 2001; P. Tookey, Ph.D., Center of Paediatric Epidemiology and Biostatistics, Institute of Child Health, London, personal communication, April 2001), and Sweden and Germany (G. Enders, M.D., Laboratory of Enders and Partners, and Institute for Virology, Infectology, and Epidemiology, personal communication, September 2001) on 680 live births to susceptible women who were inadvertently vaccinated 3 months before or during pregnancy with one of three rubella vaccines (HPV-77, Cendehill, or RA 27/3). None of the infants was born with CRS. However, a small theoretical risk of 0.5% (upper bound of 95% confidence limit = 0.05%) cannot be ruled out. Limiting the analysis to the 293 infants born to susceptible mothers vaccinated 1-2 weeks before to 4-6 weeks after conception, the maximum theoretical risk is 1.3%. This risk is substantially less than the greater than or equal to 20% risk for CRS associated with maternal infection during the first 20 weeks of pregnancy.
Measles-mumps-rubella (MMR) vaccine and its component vaccines should not be administered to women known to be pregnant. Because a risk to the fetus from administration of these live virus vaccines cannot be excluded for theoretical reasons, women should be counseled to avoid becoming pregnant for 28 days after vaccination with measles or mumps vaccines or MMR or other rubella-containing vaccines.
The goal of the U.S. rubella vaccination program is to prevent congenital rubella infection. ACIP recommended that MMR vaccine should be offered to all women of childbearing age (i.e., adolescent girls and premenopausal women) who do not have acceptable evidence of rubella immunity.
Most rubella cases in the United States occur among young Hispanic adults born outside the United States,2 and most infants with CRS are born to foreign-born mothers. Ensuring immunity in women of childbearing age, especially those at highest risk for exposure, will help to prevent CRS.
Revised ACIP Recommendation for Avoiding Pregnancy After Receiving a Rubella-Containing Vaccine. JAMA. 2002;287(3):311-312. doi:10.1001/jama.287.3.311-JWR0116-3-1