The effect of prepubertal, androgen exposure on adult penile length

Purpose: Recent studies in the rat suggest that early exposure to exogenous testosterone accelerates the loss of androgen receptors and compromises eventual penile length. To determine whether this is true in men we measured adult penile length of patients treated in childhood for sexual precocity. Materials and Methods: We examined 21 men with sexual precocity due to true precocious puberty (12) or congenital adrenal hyperplasia (9) who had been followed at our institution since childhood. Penile lengths were compared with data from normal men. Results: Mean stretched penile length plus or minus standard deviation was 12.7 +/- 2.6 cm. in all patients, 12.1 +/- 2.6 cm. in those with true precocious puberty and 13.6 +/- 1.6 cm. in those with congenital adrenal hyperplasia. These lengths were not significantly different from those of normal men (12.4 +/- 2.7 cm.). Conclusions: In contrast to findings in rats, exposure to endogenous testosterone during gestation and/or childhood does not reduce adult penile length in men. Thus, the use of testesterone to treat childhood genitourinary anomalies would likely not compromise mature penile size.