Content written by Irwin Goldstein MD


Micropenis describes an unusually small sized penis, usually less than 2 standard deviations smaller than the mean human penis size, in both stretched length from the pubic bone to the glans and in girth or circumference. Micropenis is used when the scrotum and perineum are without ambiguity. Micropenis can occur associated with hormonal abnormalities such as conditions of reduced testosterone production or effect including abnormal testicular development such as testicular dysgenesis, Klinefelter’s syndrme, or specific defects of testosterone or dihydrotestosterone synthesis, or androgen insensitivity syndromes from androgen receptor polymorphisms, or other forms of hypogonadism. Micropenis can also occur as a sign of growth hormone deficiency or hypopituitary abnormalities. If hormonal issues are identified, micropenis can often be treated in infancy with injections of human chorionic gonadotropin or testosterone. Some boys referred for micropenis do not have the micropenis condition but have a small sized penis concealed in suprapubic fat around the mons pubis.