Gynecomastia (guy-nuh-koh-MAS-tee-uh) is swelling of the breast tissue in boys or men, caused by an imbalance of the hormones estrogen and testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly.
It’s normal. Seventy percent of boys get it during puberty. It’s caused by natural changes in estrogen (a "female hormone" that men also have) and testosterone. Newborn babies sometimes have Author: Stephanie Booth.
Gynecomastia is an enlargement or swelling of the breast tissue in males. It is most commonly caused by too much influence from estrogen and not enough testosterone. In addition to breast enlargement, most male patients will experience breast tenderness and/or pain. In some cases, patients can also have nipple discharge.
What Causes Breast Enlargement in Men? A decrease in the hormone testosterone usually with an increase in the hormone estrogen cause most cases of breast enlargement in men.