The most common cause of ambiguous genitalia in a newborn is -
Ans. is 'a' i.e., 21 hydroxylase deficiency o Congenital adrenal hyperplasia due to classic 21-Hydroxylase deficiency is the most common cause of ambiguous genitalia in the newborn. Virilization is apparent at bih in the female and within the first 2-3 years of life in the male.
21 hydroxylase deficinece
11 beta - hydroxylase deficiency
17 alpha - hydroxyalse deficiency
3 beta - hydroxysteroid deficiency