Signs of hyperestrogenism may include heightened levels of one or more of the estrogen sex hormones (usually estradiol and/or estrone ), lowered levels of follicle-stimulating hormone and/or luteinizing hormone (due to suppression of the hypothalamic–pituitary–gonadal axis by estrogen), and lowered levels of androgens such as testosterone (generally only relevant to males).  Symptoms of the condition in women may consist of menstrual irregularities , amenorrhea , abnormal vaginal bleeding , and enlargement of the uterus and breasts .   It may also present as isosexual precocity in children   and as hypogonadism , gynecomastia , feminization , impotence , and loss of libido in males.  If left untreated, hyperestrogenism may increase the risk of estrogen-sensitive cancers such as breast cancer later in life.
Thomas Perls and David J. Handelsman, in a 2015 editorial in the Journal of the American Geriatrics Society , say that between the ill-defined nature of the diagnosis and the pressure and advertising from drug companies selling testosterone and human growth hormone, as well as dietary supplement companies selling all kinds of "boosters" for aging men, the condition is overdiagnosed and overtreated .  Perls and Handelsman note that in the US, "sales of testosterone increased from $324 million in 2002 to $2 billion in 2012, and the number of testosterone doses prescribed climbed from 100 million in 2007 to half a billion in 2012, not including the additional contributions from compounding pharmacies, Internet, and direct-to-patient clinic sales."