(ERT) The therapeutic use of estrogen to stop the effects of menopause after the ovaries have been removed or have stopped functioning. If the uterus is still present the hormone regimen must include at least 11 days' progestogen usage each month, or there will be a risk of endometrial hyperplasia and hence endometrial cancer.

(HRT) This could literally be the replacement of any naturally deficient hormone, but in practice it means estrogen replacement therapy.

Hormone replacement therapy; see estrogen replacement therapy.

(PMT) A distressing group of symptoms usually timed for the lead up to a period, then relieved as menstruation takes place, although many women experience different timing; includes downheartedness or depression (certainly an absence of well-being), aggression, fluid retention and weight gain, painful breasts ('mastalgia'), headaches and pain in the pelvis; caused by a periodic fall in the brain's endorphins, in turn usually precipitated by falling levels of progesterone in the second half of the luteal phase, although similar symptoms often accompany the use of progestogens, especially in older women; may be better during superovulation cycles because of generally higher hormone levels, but this is not always the case and PMT at the end of an unsuccessful cycle of assisted conception is particularly hard to put up with. Usually treated (up to a point) symptomatically, with perhaps fluid tablets (diuretics) and analgesics, although it's claimed that the drug Prozac has a specifically beneficial effect on mood, and encouragement of endorphin release with exercise can also be useful. Because progesterone and progestogens are the culprits, an operation to remove the ovaries (plus hysterectomy to simplify estrogen replacement therapy without needing progestogens) is usually curative, but drastic.

Failure of the ovaries to produce enough follicles, because of a problem in the ovary itself, and resulting in depletion of eggs before the age of 40 years (known as premature menopause, a cause of secondary amenorrhea), or maybe even before the age puberty is expected (causing failure of puberty to happen, including primary amenorrhea). Sometimes occurs in spite of good numbers of primordial follicles that (inexplicably, so far) won't develop. The younger the woman, the more likely that an aneuploidy will be found if a karyotype is done on blood or on a biopsy of the ovary. Estrogen replacement therapy is important to prevent general jeopardy to health, including prevention of osteoporosis.