Antibodies against Ro or La can be transferred from mother to child through the placenta. These antibodies may cause neonatal lupus, whose most serious manifestation is congenital heart block. In many cases the mother is asymptomatic and only later, if at all, does she develop a manifest autoimmune disease. In most cases of verified congenital heart block the antibodies are directed against part of the Ro52 antigen called p200. When these antibodies are detected in pregnant women, the heart of the foetus is examined repeatedly by ultrasound till the 24th week of pregnancy, when the risk of developing a heart block decreases.
Indications: Pregnant women with known autoimmune disease, mainly SLE or Sjögren’s syndrome. Low heart rate in foetus in routine control. Patients who have given birth to babies with congenital heart block or myocarditis.