Shortening of the penis can be a result of weight gain and the deposition of fat around the pubic area. This results in the visual shortening of penis. Obesity increases the risk of erectile dysfunction and heavy men who complain of loss of length may simply have inadequate blood flow to achieve adequate rigidity.
Less common reasons for shortening of the penis are inborn defects in response to a male hormone (testosterone), congenital chordee (tethering of penis), chromosomal abnormalities (rare), or a scar from Peyronie's disease (development of scars/plaques in the penis). Penile length may slightly decrease with age because of atrophy related to a decrease in testosterone level and the decreased frequency of erections. Prostate surgery may also damage the nerves and result in shortening of the penis. Thus, men who are concerned about penile size should be fully evaluated by a urologist specializing in sexual medicine, to exclude medical reasons for a change in penile size.