Ans. d. 46XX/46XYRef: Williams Obstetrics 24th Ed; Page No-148-49GENITAL AMBIGUITY OF THE NEWBORNAmbiguity of the neonatal genitalia results from excessive androgen action in a fetus that was destined to be female or from inadequate androgen representation for one destined to be male.Rarely, genital ambiguity indicates true hermaphroditism.Several transcription factors--SOX9, SF1, and WT1, and disruptions of signaling molecules--hedgehog, WNT, cyclin dependent kinase, and Ras/MAP kinase--cause disorders of sexual development.Examples are congenital adrenal hyperplasia and androgen insensitivity syndrome.Abnormalities of gender differentiation causing genital ambiguity can be assigned to one of four clinically defined categories:Female pseudohermaphroditismMale pseudohermaphroditismDysgenetic gonads, including true hermaphroditism; and rarelyTrue hermaphroditism.FEMALE PSEUDOHERMAPHRODITISMIn this condition, mullerian-inhibiting substance is not produced.For a fetus genetically predestined to be a female, androgen exposure should be excessive and variable.The karyotype is 46XX with presence of ovary.Therefore, by genetic and gonadal gender, all are supposed to be female, and the basic abnormality is androgen excess. Because mullerian- inhibiting substance is not produced, the uterus, fallopian tubes, and upper vagina develop.MALE PSEUDOHERMAPHRODITISMIt is characterized by incomplete and variable androgenic exposure of a fetus supposed to be male.The karyotype is 46, XY and characterized by either presence of testes or no gonads.In some cases, incomplete masculinization follows inadequate production of testosterone by the fetal testis.It also may result from decreased responsiveness of the genital anlage to normal quantities of androgen--including failure of the in situ formation of 5a-DHT in androgen-responsive tissue.Because testes were present for at some point of embryonic life, mullerian inhibiting substance is produced. Thus, the uterus, fallopian tubes, and upper vagina do not develop.DYSGENETIC GONADSIn affected individuals, karyotype differs and is mostly abnormal. As the name describes, most have abnormally developed gonads, and streak gonads are typically present.As a result, mullerian-inhibiting substance is not produced and fetal androgen exposure is variable, which results in presence of uterus, fallopian tubes and upper vagina.Most common form of gonadal dysgenesis is Turner syndrome (46, X).The phenotype is female, but secondary sexual characters don't develop at the time of expected puberty, and genital infantilism persists.TRUE HERMAPHRODITISMIn most of the cases, category 3 guidelines are met.External genitalia are seen in such type a case.The karyotype of True hermaphroditism of an infant with 46, XX/46, XY.True hermaphrodites have both ovarian and testicular tissues with germ cells for both ovum and sperm in the abnormal gonads.AMBIGUOUS GENITALIATypeKaryotype and featuresFigureFemalepseudohermaphroditism*. It is caused by congenital adrenal hyperplasia*. The karyotype of Infant 46,XX*. Features: Severe virilization with scrotal formation without a testis and a penile urethra are seen in this caseMale pseudo hermaphroditism*. It is caused by incomplete androgen insensitivity syndrome*. Karyotype of Infant is 46, XY*. Features: External genitalia demonstrating clitoral hypertrophyTrue hermaphroditism *. True hermaphroditism in an infant with 46, XX / 46, XY*. A hemiscrotum is seen and there are different skin tones on each side