Management of fetal congenital heart block in pregnancies with anti-Ro antibodies

Anti-Ro antibodies are detected frequently in the general population, but more so in patients with autoimmune conditions as Sjögren’s syndrome and systemic lupus erythematous (SLE). During pregnancy, anti-Ro antibodies can cross the placenta by hijacking physiological mechanisms and can have deleterious effects on the fetus. Administration of hydroxychloroquine (HCQ) to pregnant women with documented anti-Ro antibodies has been shown to prevent congenital heart block (CHB). Serial fetal ultrasound scans and echocardiograms are controversial in pregnant women with anti-Ro antibodies. When complete CHB is diagnosed, this is irreversible and can lead to fetal heart failure, hydrops, and death. After delivery, babies with complete CHB require pacemaker. In the presence of maternal anti-Ro antibodies, there is a high risk of recurrence of CHB for future pregnancies, if there is a previously affected child. Adequate counselling and prophylactic treatment with HCQ should be encouraged.