Hyperestrogenism

Hyperestrogenism is the estrogenic version of hyperandrogenism, representing the excessive amount of estrogen in the body. Symptoms of the condition in AFAB may consist of menstrual irregularities, amenorrhea, abnormal vaginal bleeding, and enlargement of the uterus and breasts. If left untreated, hyperestrogenism may increase the risk of estrogen-sensitive cancers such as breast cancer later in life.

Causes
Hyperestrogenism can be caused by ovarian tumors, genetic conditions, such as aromatase excess syndrome/familial hyperestrogenism, or overconsumption of exogenous sources of estrogen which may include medications used in hormone replacement therapy and hormonal contraception. Liver cirrhosis is another cause, though through lowered metabolism of estrogen, not oversecretion or overconsumption like the aforementioned. It's necessary to know there exist two kinds of hyperestrogenism: Absolute (more concentration than usual of estrogen) and relative (can have a normal concentration of estrogen, but it's higher with respect to progesterone).