Ambiguous Genitalia | Symptoms & Causes

What are the characteristics of ambiguous genitalia?

Your obstetric team will most likely be the first ones who notice the ambiguous genitalia. They may see the following:

Characteristics of ambiguous genitalia in genetic females include:

  • an enlarged clitoris, or what appears to be a small penis
  • a concealed vagina

Characteristics of ambiguous genitalia in genetic males include:

  • hypospadias, the condition in which the narrow tube that carries urine and semen (urethra) doesn't fully come to the tip of the penis
  • an abnormally small penis with the urethral opening nearer to the scrotum
  • no recognizable male genitalia in the most severe cases
  • the absence of both testicles in what appears to be the scrotum

What causes ambiguous genitalia?

The sexual organs of males and females develop from the same fetal tissue. The same tissue that becomes a penis in a male becomes a clitoris in a female. The main factor controlling the next step is male hormones. The presence of male sex hormones causes male organs to develop and the absence of male hormones causes female organs to develop.

Without enough male hormones, a genetic male will develop ambiguous genitalia. Likewise, a genetic female will develop ambiguous genitalia if male hormone is present.

Possible causes of ambiguous genitalia in genetic females:

  • certain forms of congenital adrenal hyperplasia (CAH), the most common cause of ambiguous genitalia in newborn females, which cause the adrenal glands to make excess male hormones (androgens) 
  • mother's ingestion of a substance with male hormone activity, like progesterone (taken in the early stages of pregnancy to stop bleeding)
  • tumors in the fetus of the mother that produce male hormones.

Possible causes of ambiguous genitalia in genetic males:

  • impaired testicle development caused by genetic abnormalities or unknown causes
  • leydig cell aplasia, a condition that impairs testosterone production
  • androgen insensitivity syndrome 
  • 5alpha-reductase deficiency: An enzyme deficiency that impairs normal male hormone production.

  • the mother's ingestion of substances with female hormone activity, for example, estrogens, or anti-androgens