Therapeutic abortions following rubella infection in pregnancy: the potential impact on the incidence of congenital rubella syndrome.

In 1977, a large rubella outbreak occurred in Hawaii. Because attack rates were high among women of childbearing age, we conducted extensive surveillance efforts to detect both pregnancies complicated by rubella and cases of congenital rubella syndrome (CRS). Initial surveillance included a survey of physicians and hospitals, review of fetal death and birth certificates, and cord blood screening for rubella-specific IgM of infants born following the epidemic. Two years after the outbreak, the medical community was again surveyed to identify affected children who were missed initially. No case of CRS was identified either shortly after the outbreak or in the ensuing two years. In addition, none of the 5,605 cord serum samples obtained was found to contain rubella-specific IgM antibody. Through active surveillance, we received 12 reports of rubella in pregnant women, of whom 11 elected to terminate their pregnancies. The extensive use of therapeutic abortion by exposed women may have prevented the birth of infants with CRS. Surveillance for rubella-related abortions is an important component in assessing the health impact of rubella in a community.