In genetic terms, CAH is autosomal recessive, which means that if both parents are carriers, the chances are 1 in 4 that their child will have the disease. The chances are also 1 in 2 that their child will be female. Together, that means the chances are 1 in 8 that the child will both have CAH and be female. Or: they are 7 in 8 that the child either won’t have CAH or will be a boy.