We know that the standard Myotonic Dystrophy is among the most common of Muscular Dystrophies with an incident of 1 in 7000 or 1 in 8000 (from MDA USA).   In the Saquenay region of Quebec, myotonic dystrophy incident is 1 in 500. It is the most frequent diagnosis of the MDA of Canada. Almost 19% have the disorder of the patients of MDA Canada- almost double the incidence of Duchenne Muscular Dystrophy.

Harper estimated the incidence of Congenital myotonic dystrophy as 1 in 100,000 and Wales and Wesstrom reported an incidence of congenital myotonic dystrophy of 1 in 3500 in Sweden. The coastal region of Norrbotten, Sweden has an exceptionally prevalence of myotonic dystrophy. About 95,000 people live in this area (Forsberg H. 1990)

If Harpers numbers are correct this would translate into an estimated 2,500 individuals with the congenital form in the United States and about 60,000 world wide.

Information from England indicates that the incidence in European Populations is about 1/20,000.

The incidence of the Congenital Muscular Dystrophy form is more difficult to tell. Kobayashi reports the incident of 6.9-11.9 X 10(-5) for FCMD. The incident of MP-CMD is estimated at 3.45-5.95 X 10(-5) The last two figures from Kobayashi are the incidence of the disease in Japan.

Another statistic from MDA USA Technical Bulletin #77 FUKUYAMA-TYPE CONGENITAL MUSCULAR DYSTROPHY (FCMD) is the most common autosomal recessive disorder in Japan with an incidence of 0.7-1.2/100,000 births.