Rubella infection during pregnancy in the 1985-86 epidemic: follow-up after seven years.

The study covered 310 pregnant women from southern Poland who were exposed to rubella during the 1985-86 epidemic, none of whom had been vaccinated against rubella. Rubella specific antibodies were detected by hemagglutination-inhibition (HI) tests, and IgM antibodies by enzyme immunoassay (ELISA) (Organon Teknika). Clinical symptoms according to anamnesis were recorded. The consequences of serologically confirmed maternal rubella on the course of pregnancy and on fetal outcome were evaluated. IgM antibodies could be examined in only 10 newborns at delivery or in the first days of life. After seven years, follow-up studies of children born to infected mothers were done. The mental development of 14 of these children was evaluated with Terman-Merrill test. Among 310 women examined during pregnancy, rubella infection was confirmed serologically in 46 cases (14.8%). All but 3 of those had clinical symptoms. The course of pregnancy was observed in 36 of the infected mothers. Only 5 women (22.7%) who had the infection in the first trimester of pregnancy delivered a healthy child. The rate of complications in pregnancy among women infected in the second trimester was lower, and 8 (66.7%) bore healthy children. All the children born to mothers infected in the third trimester were healthy. Eight of the 10 newborns examined at delivery were IgM positive. Of 29 children congenital rubella syndrome (CRS) was confirmed in 5 cases, CRS compatible or CRS possible in 7 and 3 had congenital infection only confirmed serologically (IgM-positive) without defects or symptoms. Seventeen (58.6%) children were found healthy including the 3 who had congenital infection only. The mental development of 14 children at age 7 was assessed; 10 cases (72%) fell within rank II 130-85, and 4 (28%) were of borderline intelligence. The study indicates that congenital rubella is still a serious problem in Poland. Immunization was introduced only in 1988-89, for 13-year-old girls. Women of child-bearing age should be screened for rubella antibodies and those susceptible to rubella infection should be vaccinated.