It can be revealed from the study findings that: (1) It is essential that heterozygous carriers among family members with CAH caused by 21-hydroxylase deficiency be detected in order to work out managing, monitoring and treatment plans as well as stipulate genetic counseling; (2) It is necessary to perform prenatal diagnosis for all cases of pregnant women, who are identified as the carriers and at high risk for giving birth with ill children, so as to advise their families and provide doctors with an early treatment plan for the fetus and after birth.