It can be due to testosterone deficiency, pituitary hormone deficiency, hypergonadotropic hypogonadism and
growth hormone deficiency. Various investigations required are chromosomal studies, hormone studies like Gonadotropins (LH and FSH), Testosterone and DHT levels, thyroid hormone lvels, ultrasonography and testosterone therapy. Three kinds of exercises are there for increasing the penis size which have proved little benefit. They include jelqing, penis stretching and kegel exercises.