Autoantibodies against 52/60kD-Ro proteins, frequently present in patients with Sjoegren's Syndrome or systemic lupus erythematosus, are transmitted to the fetus during pregnancy. These autoantibodies can damage the cardiac conductive system of the fetus and cause a complete atrioventricular block, with a mortality of 30 %. We report the intrauterine therapy during four pregnancies of the same mother with high 52/60kD-Ro autoantibodies and the outcome of her infants. Our patient with primary Sjoegren's Syndrome suffered an early miscarriage during her first pregnancy. During the second pregnancy, a fetal atrioventricular block was observed at 23 weeks of gestation. Although subsequently dexamethasone therapy and daily plasmaphereses were started, a cesarean section was necessary at 26 weeks due to hydrops fetalis. The girl died from the atrioventricular block after two days. During the third and fourth pregnancies, dexamethasone therapy was begun already at 7 weeks, and regular plasmaphereses at 15 weeks. The children were delivered by cesarean section at 32 and 36 weeks because of growth retardation. Both had normal electrocardiograms after birth and after 2 and 4 years. In pregnant women with connective tissue diseases, monitoring of anti Ro-autoantibodies and fetal heart function is important. Intrauterine therapeutic options are dexamethasone therapy to suppress maternal and fetal inflammatory reactions and repeated plasmaphereses to reduce autoantibody levels. Postnatal follow up of the infants for atrioventricular block and rheumatic manifestations is necessary.