Increased risk for abnormal placentation in women affected by myotonic dystrophy.

The obstetric histories of 26 women with myotonic dystrophy, who had a total of 66 life births, were reviewed by means of questionnaires and medical reports. Six patients (23%) each had one pregnancy complicated by placenta praevia (affecting 9% of all completed pregnancies), pointing toward a susceptibility to abnormal placentation in this disorder. As involvement of the genitourinary tract is common in myotonic dystrophy, an increased risk for placenta praevia has to be considered in the antenatal care of these patients.