Gynaecomastia

Gynecomastia (guy-nuh-koh-MAS-tee-uh) is an increase in the amount of breast gland tissue in boys or men, caused by an imbalance of the hormones estrogen and testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly.

Pseudogynecomastia refers to an increase in fat but not glandular tissue in male breasts.

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.

Generally, gynecomastia isn't a serious problem, but it can be tough to cope with the condition. Men and boys with gynecomastia sometimes have pain in their breasts and may feel embarrassed.