Outcome of rubella during pregnancy with special reference to the 17th-24th weeks of gestation

The consequences of rubella during pregnancy were studied with special reference to infections occurring during the 17th to 24th weeks of gestation. Laboratory confirmed rubella infected pregnancies were followed and the infants were examined clinically and serologically at a mean age of 20 months. In addition children born to mothers with verified rubella in earlier epidemics were examined clinically at the age of 4 or 7 yr. 491 cases of rubella in pregnant women from 1978-1980 were reported and 118 children were followed-up. Intrauterine transmission occurred in greater than 50% during the 16 first weeks of pregnancy compared to in 17% during the 21st to 24th weeks. Rubella defects appeared in a declining rate from 5/6 congenitally infected during the first 12 weeks to 1/7 at weeks 15 and 16. Three cases with deafness were found among the 65 children from earlier epidemics. Only 1 child with hearing impairment was found among children whose mothers were infected after the 16th week. Although rubella infections during the 17th to 24th weeks of pregnancy result in transmission to the fetus in about one fifth, sequelae seem to be a rare event.