+12 Causes Of Gynecomastia Ideas. Web gynecomastia is thought to be caused by an altered ratio of estrogens to androgens mediated by an increase in estrogen action, a decrease in androgen action, or a combination of these two factors. Steroids, such as prednisone or dexamethasone.

A decrease in the hormone testosterone, usually with an increase in the hormone estrogen, causes most cases of gynecomastia. However, it has been proven to be associated with imbalances in the hormones estrogen and testosterone. If you're overweight you're also more likely to have.