PATHOLOGIC GYNECOMASTIA: INCREASED ESTROGEN Since the development of breast tissue in males occurs in an analogous manner to that in females, the same hormones that affect female breast tissue can cause gynecomastia. The testes secrete only 6-10 mg of estradiol and 2.5 mg of
estrone per day. Since this only comprises a small fraction of estrogens in circulation (i.e. 15% of estradiol ...