Fetal Macrocephaly: A Novel Sonographic Finding in Congenital Myotonic Dystrophy.

 Sonographic clues to the diagnosis of congenital myotonic dystrophy (CDM) are limited, particularly in the absence of family history of myotonic dystrophy (DM). We reviewed cases of CDM for unique prenatal findings.  A single-center case series of fetuses with CMD with characteristic prenatal findings confirmed postnatally.