Ambiguous genitalia is a birth defect where the outer genitals do not have the typical appearance of either a boy or a girl.
Genitals - ambiguous
The genetic sex of a child is determined at conception. The mother's egg cell (ovum) contains an X
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. The genitalia makes it difficult to easily identify the infant as male or female. The extend of the ambiguity varies. In very rare instances, the physical appearance may be fully developed asthe opposite of the genetic sex. For example, a genetic male may have developed the appearance of a normal female.
Typically, ambiguous genitalia in genetic females (babies with two X chromosomes) has the following features:
- An enlarged clitoris that looks like a small
- The urethral opening (where urine comes out) can be anywhere along, above, or below the surface of the clitoris.
- The labia may be fused and look like a
- The infant may be thought to be a male with undescended
- Sometimes a lump of tissue is felt within the fused labia, further making it look like a scrotum with testicles.
In a genetic male (one X and one Y chromosome), ambiguous genitalia usually include the following features:
- A small penis (less than 2 - 3 centimeters or3/4 to 1 1/4inches) that looks like an enlarged clitoris (the clitoris of a newborn female is normally somewhat enlarged at birth).
- The urethral opening may be anywhere along, above, or below the penis. It can be located as low as on the peritoneum, further making the infant appear to be female.
- There may be a small scrotum that is separated and looks like labia.
- Undescended testicles commonly occur with ambiguous genitalia.
Ambiguous genitalia is usually not life threatening (see Causes section for exceptions), 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.
Pseudohermaphroditism. The genitalia are of one sex, but some physical characteristics of the other sex are present.
- True hermaphrodism.This is avery rare condition, in which tissue from both the ovaries and testicles is present. The child may have parts of both male and female genitals.
- Mixed gonadal dysgenesis (MGD).This is anintersex condition, in which there are some male structures (gonad, testis), as well as a uterus, vagina, and fallopian tubes.
Congenital adrenal hyperplasia. This condition has several forms, but the most common form causes the genetic female to appear male. Many states test for this potentially life-threatening condition during newborn screening exams.
- Chromosomal abnormalities, including
Klinefelter's syndrome(XXY) and Turner's syndrome(XO).
- If the mother takes certain medications (such as androgenic steroids), they may make a genetic female look more male.
- Lack of production of certain hormones can cause the
embryoto develop with a female body type, regardless of genetic sex
- Lack of
testosteronecellular receptors. Even if the body makes the hormones needed to develop into a physical male, the body cannot respond to those hormones. This produces a female body-type, even if the genetic sex is male.
Because of the potential social and psychological effects of this condition, parents should make a decision about whether to raise the child as a male or female early after diagnosis, preferably within the first few days of life. This is an important decision, so parents should not rush it.
Call your health care provider if
You are concerned about the appearance of your child's external genitalia, or your baby:
- Takes more than 2 weeks to regain his or her birth weight
- Is vomiting
- Looks dehydrated (dry inside of mouth, no tears when crying, less than 4 wet diapers per 24 hours, eyes look sunken in)
- Has a decreased appetite
- Has blue spells
- Has trouble breathing
These can all be signs of
Ambiguous genitalia may be discovered during the first
What to expect at your health care provider's office
The doctor will perform a physical examination, which may reveal genitals that are not "typical male" or "typical female," but somewhere in between.
The doctor will ask medical history questions to help identify any chromosomal disorders. Questions may include:
- Is there any family history of
- Is there any family history of
- Is there any family history of early death?
- Have any family members had infants who died in the first few weeks of life or who had ambiguous genitalia?
- Is there any family history of any of the disorders that cause ambiguous genitalia?
- What medications did the mother take before or during pregnancy (especially steroids)?
- What other symptoms are present?
Genetic testing can determine if the child is a genetic male or female. Often a small sample of cells can be scraped from inside the child'scheeks (this is called a
Laboratory tests may help determine how well the reproductive organs are functioning. This can include tests for adrenal and gonadal steroids.
In some cases,
Depending on the cause, surgery, hormone replacement, or other treatments are used to treat conditions that can cause ambiguous genitalia.
Sometimes, the parents must choose whether to raise the child as male or female (regardless of the child's chromosomes). This choice can have a big social and psychological impact on the child, so counseling is usually recommended.
Note: It is often technically easier to treat (and therefore raise) the child as female (it is easier for a surgeon to make female genitalia than it is to make male genitalia), so in some cases this is recommended even if the child is genetically male. However, this is a difficult decision. Youshould discuss it with your family, your child's doctor, the surgeon, your child's endocrinologist, and other health care team members.
Diamond AD, Yu RN. Sexual differentiation: Normal and abnormal. In: Wein AJ, ed. Campbell-Walsh Urology. 10th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 133.