Virilization is when a female develops male sex characteristics, or a newborn boy has increased male characteristics at birth.

Virilization may be caused by:

• Excess testosterone production
• Use of anabolic steroids

In newborn girls, the condition may be caused by:

• Certain medications taken by the mother during pregnancy
• Congenital adrenal hyperplasia in the baby or her mother
• Other medical conditions in the mother (such as tumors of the ovaries or adrenal glands that release male hormones)

Signs of virilization in a female may include:

• Deepening of the voice
• Facial hair
• Increase in body hair
• Male-pattern baldness
• Swelling of the clitoris

Tests may include:

• Blood tests to detect excess testosterone in females
• CT scan, MRI, or ultrasound to rule out tumors of the ovaries and adrenal glands

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