PIP: Current opinion is that pregnancy should be avoided for 2-3 months after rubella vaccination because of the possible teratogenic potential of the vaccine. The possible risk of conception soon after vaccination was explained to 866 women found to be seronegative for rubella. Vaccine was administered to those sexually active only if they had used a reliable method of contraception (pill, IUD, and condom or diaphragm with spermicidal agents) for the previous month, and who consented in writing to continue for 3 more months. IUD users were also advised to use a spermicide in addition. 34% of women were on oral contraception, 14% used the condom, 5% had an IUD, 2% used the diaphragm, and 30% were not at risk of pregnancy. Counseling prior to vaccination resulted in the initiation of contraception in 7 sexually active women. Vaccination was never timed with a menstrual period.