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Genitals - ambiguous
Ambiguous genitalia is a birth defect where the outer genitals do not have the typical appearance of either a boy or a girl.
See also: Genetics
The genetic sex of a child is determined at conception. The mother's egg cell (ovum) contains an X chromosome, while the father's sperm cell contains either an X or a Y chromosome. These X and Y chromosomes determine the child's genetic sex.
Normally, an infant inherits one pair of sex chromosomes -- one X from the mother and one X or one Y from the father. The father "determines" the genetic sex of the child. A baby who inherits the X chromosome from the father is a genetic female (two X chromosomes). A baby who inherits the Y chromosome from the father is a genetic male (one X and one Y chromosome). The male and female reproductive organs and genitals both come from the same tissue in the fetus.
If the process that causes this fetal tissue to become "male" or "female" is disrupted, ambiguous genitalia can develop. This genitalia makes it difficult to classify the infant as male or female. In very rare instances, the physical appearance may be the opposite of the genetic sex. For example, a genetic male may have the appearance of a normal female.
Usually, ambiguous genitalia in genetic females (babies with two X chromosomes) has the following features:
In a genetic male (one X and one Y chromosome), ambiguous genitalia usually include the following features:
Ambiguous genitalia is usually not life threatening, but it can create social problems for the child and family. For this reason, a team of experienced specialists, including neonatologists, geneticists, endocrinologists, and psychiatrists or social workers will be involved in the child's care.
Diamond DA. Sexual differentiation: Normal and abnormal. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 128.
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