Newborns, boys going through puberty and older men may develop gynecomastia as a result of normal changes in hormone levels, though other causes also exist. In girls, breast growth is caused by high levels of estrogen. Bannayan et al 20 have described three histological types of gynecomastia:
Morselli P G, Morellini A. Bidlingmaier F, Knorr D.
A detailed history should focus on time of onset and duration of the gynecomastia, associated symptoms e. Treatment is geared toward the specific etiology when identified.