Congenital adrenal hyperplasia: is there an effect on penile growth?

Experimental evidence in rodents suggests that prepubertal exposure to excess androgens may prematurely down regulate the penile androgen receptor and cause micropenis in adulthood. To evaluate the effect of prepubertal androgens on human penile growth we reviewed phallic development in male patients with congenital adrenal hyperplasia.

We retrospectively reviewed the records of 12 patients with 21-hydroxylase deficiency. Stretched penile length was recorded at diagnosis and at last followup. Bone age, height and weight were recorded at each visit.

At diagnosis mean z-score for stretched penile length (z-score equals the number of standard deviations above or below the mean, that is z-score for micropenis equals -2.5) was 2.95 (1.23 to 4.88). Final mean z-score for stretched penile length in adulthood was -1.70 (-2.96 to 1.87). Mean decrease in z-score for diagnosis until the last followup was -4.68 (-1.08 to -6.82). Only 2 of the 12 patients (17%) had micropenis in adulthood. Notably excessive adrenal androgen production resulted in diminutive stature with median height in adulthood in the 10th percentile.

These findings suggest that excessive prepubertal androgen exposure due to congenital adrenal hyperplasia is associated with a reduction in adult somatic height but it does not routinely result in micropenis.