Congenital disorders of glycosylation type Ia as a cause of mirror syndrome.

Mirror syndrome (that is fetal hydrops with subsequent edema in the pregnant woman) is a rare condition. Early diagnosis is warranted, as maternal and fetal morbidity and mortality is increased if not diagnosed and treated properly. In most cases, the underlying cause remains unclear. We report a woman who has had two pregnancies complicated by mirror syndrome. Congenital disorder of glycosylation type Ia (CDG-Ia) was identified as the underlying fetal disease in both cases.