Prenatal diagnosis of disorders of galactose metabolism.

Of three clinically significant galactose disorders, there is only a real need and experience of prenatal diagnosis in classical galactosaemia. Prenatal diagnosis for this disorder may be carried out by galactose-1-phosphate uridyl transferase assay in cultured amniotic fluid cells or in chorionic villus biopsies and by galactitol estimation in amniotic fluid supernatant. Although the long-term outcome of patients treated on a galactose-restricted diet is recognized to be unsatisfactory, prenatal diagnosis is only rarely performed with a view to terminating the affected pregnancy.