Dermal fat grafting (DFG) involves the extraction of a patch of skin from the patient's own body (usually the lower back, lower abdomen, or buttocks) along with a layer of fat. After the skin is removed from the penis, the extracted tissue is grafted in its place. Because the extracted skin is thicker, it will increase the circumference of the penis. By taking tissue from the patient's own body, the risk of rejection is low.
Stretching with weights. Weights or stretching exercises won't bulk up your penis -- it's not a muscle. But hanging weights off your flaccid penis may stretch it a bit, O'Leary says. The catch is that it requires a freakish degree of dedication. "You might have to wear a weight strapped to your penis eight hours a day for six months," says O'Leary. At the end of it, you could be lucky enough to gain about half an inch. Risks include tearing of the tissue, burst blood vessels, and other problems.