QUESTIONMy 22-year-old patient immigrated to Canada 6 years ago from a country where there are no routine immunizations. She is now at 10 weeks' gestation and was exposed to a child with rubella infection. Her immune status is unknown. Should I give her passive or active immunization? How should I follow her pregnancy? And what should I tell her about the risk for her fetus?ANSWERIf the exposure took place less than 1 week ago, blood should be sent for rubella antibody titre. If results are positive for IgG, she is immune and there is no risk for the fetus. If a patient's immune status is unknown and the time of exposure is uncertain, serum samples for rubella antibodies should be obtained 3 weeks apart. Detection of rubella-specific IgM in a sample will confirm recent infection. Your patient should be counseled about the potential risk for her fetus and referred to high-risk pregnancy clinic for follow up. If seroconversion does not take place, she requires immunization immediately postpartum before discharge from hospital.