Some men are born with what’s called a micropenis, defined by the American Urological Association as a stretched penile length of 7.5 centimeters or less. Micropenis is a condition with varying degrees of severity and may include a hormonal imbalance. Having a micropenis does not necessarily make you a good candidate for any or all penis enlargement surgeries.
The vacuum pump. This is a cylinder that sucks out air. You stick your penis in and the resulting vacuum draws extra blood into it, making it erect and a little bigger. You then clamp off the penis with a tight ring -- like a tourniquet -- to keep the blood from leaking back into your body. What are the drawbacks? The effect only lasts as long as you have the ring on. Using it for more than 20 to 30 minutes can cause tissue damage. This is sometimes used as a treatment for erectile dysfunction, but has not been proven to actually increase the size of the penis.