① Genetic factors. The size of penis is controlled and influenced by genetic genes.

② Poor development and poor nutritional status. Strong and tall men have well-developed external genitalia, and their penises may be larger, and vice versa, but the penis size is not necessarily proportional to their height.

③ Obesity. If the lower abdomen, pubic symphysis and perineum are full of fat, the penis is often stunted and the penis will be shorter.

④ Other factors. Such as endocrine disorders, insufficient androgen level, penis "retraction" caused by testicular or scrotal swelling, etc. , can lead to short penis.

At present, the treatment of small penis in clinical medicine is mainly surgery, which can achieve two purposes, one is to lengthen the penis and the other is to thicken the penis. After the operation, the short penis can generally grow 2-4 cm. For some small penis patients with impotence, silicone rubber strips can be inserted between two penis sponges to make the penis bigger and thicker. The advantage is that the operation method is relatively simple and safe, but some people may feel foreign body sensation in the penis after operation.

The short-term non-surgical treatment of penis is injection of fat particles, which makes the penis attract and pull by negative pressure, thus increasing the arterial blood supply of penis, filling the cavernous tissue of penis, limiting venous reflux, and thus making the penis grow continuously. The endocrine function of patients is required to be normal, especially the serum testosterone level should be within the normal range. It is an ideal non-surgical plastic surgery method that combines physical therapy with psychotherapy and does not interfere with endocrine function.