Because congenital muscular dystrophy occurs so early in childhood, the first step in diagnosis is often a physical exam and a review of symptoms. Then a doctor may perform one of several tests depending on the type of congenital muscular dystrophy suspected and also depending on the age and condition of the child. Blood tests can analyze levels of certain enzymes that indicate congenital muscular dystrophy and in some cases, blood samples can also be used for DNA testing. Electromyography, which involves inserting a very thin electrode into your muscle, can test electrical activity in muscles. Muscle biopsy, which involves removing a small sample of muscle tissue to be analyzed under a microscope, can test for certain indicators of congenital muscular dystrophies. However, since little is known about certain types of congenital muscular dystrophy, the diagnosis process may be complex and difficult.