Hi! Although there are different types of dwarfism.....dwarfism is primary a bone-structure deformity of the long bones of the body. In general, the soft tissues are unaffected. This is not to say that you would not find the same normal variation in the genitals of a person with dwarfism as you would in the general population (ranging from very small to very large). You can expect that a dwarf would have an average size genitalia. Normally, the trunk is unaffected (that being where the penis is located) and it is the limbs which are shorter than normal.
Let me know if you need more information! Donna RN