[Polyhydramnios in congenital myotonic dystrophy].

A case of hydramnion by congenital myotonic dystrophy is presented. By a 31 years old primipara typical causes of hydramnion as fetal malformations, immunologic or non-immunologic hydrops, diabetes mellitus or intrauterine infections could be excluded. Because of a severe fetal dystrophy with imminent asphyxia a caesarean section has been performed in the 35th. week of pregnancy. The newborn showed all clinical symptoms of congenital myotonic dystrophy and died after four weeks in a respiratory distress. A muscle biopsy of the m. quadriceps confirmed the diagnosis. EMG examination of the parents revealed a conductoring state of the mother. Possible causes of "idiopathic" hydramnion and possibilities of prenatal diagnosis of congenital myotonic dystrophy are discussed.