Does a female-to-male sex change work?

It can be done: Female-to-male gender reassignment is harder than male-to-female because of the external genitalia and the need for erection during sex. What's harder than creating the penis from flaps and erasing any signs of female breasts, however, is making sure that the person really is ready for the change. This requires a long period of living as a male while undergoing counselling and hormone treatments.

Tummy, wrist, etc: There are a variety of possible donor sites but the two most common are the abdomen which can be supplemented with the use of a tissue expander. However another popular option is the use of forearm skin which is transplanted to the genital area using micro vascular techniques.