These hormones don't cause the sex glands to mature but do cause a child to look more like an adult. In both true precocious and pseudoprecocious puberty, a boy develops facial, underarm, and pubic hair. His penis lengthens, and his appearance becomes more masculine. A girl may start to have menstrual periods, especially if she has true precocious puberty, or she may develop breasts, pubic hair, and underarm hair. In boys and girls, body odor changes, and acne may appear.
Height increases rapidly but stops at an early age.
Therefore, the final height is shorter than had been expected. In true precocious puberty, but usually not in pseudoprecocious puberty, the testes or ovaries enlarge to adult size. Diagnostic tests include measuring blood hormone levels and taking x-rays of the hand and wrist to estimate bone maturity. The antifungal agent ketoconazole reduces the levels of testosterone circulating in the blood in boys who have testotoxicosis. A drug called testolactone reduces the levels of estrogen in adolescents who have McCune-Albright syndrome.