Lack of menstruation. Signs of primary amenorrhea (failure to start menstruating by age 16) include infantile reproductive organs, lack of breasts and pubic hair, dwarfism, and deficient muscle development. In secondary amenorrhea (abnormal cessation of cycles once started), the genitals atrophy and pubic hair diminishes. Not itself a disease, amenorrhea reflects a failure in the balance among the hypothalamus, pituitary gland, ovaries, and uterus; tumours, injuries, or diseases of these can lead to amenorrhea. Other causes include systemic diseases, emotional shock, stress, hormone over- or underproduction, anorexia nervosa, absence of ovaries or uterus, pregnancy, lactation, and menopause. Infrequent menstruation or amenorrhea not resulting from organic disease is not harmful.
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Amenorrhoea (BE), amenorrhea (AmE), or amenorrhœa, is the absence of a menstrual period in a woman of reproductive age. Physiologic states of amenorrhoea are seen during pregnancy and lactation (breastfeeding), the latter also forming the basis of a form of contraception known as the lactational amenorrhea method. Outside of the reproductive years there is absence of menses during childhood and after menopause.
Amenorrhoea is a symptom with many potential causes. Primary amenorrhoea (menstruation cycles never starting) may be caused by developmental problems such as the congenital absence of the uterus, or failure of the ovary to receive or maintain egg cells. Also, delay in pubertal development will lead to primary amenorrhoea. Secondary amenorrhoea (menstruation cycles ceasing) is often caused by hormonal disturbances from the hypothalamus and the pituitary gland or from premature menopause, or intrauterine scar formation.
Types of amenorrhoea is diagnosed based on several factors which include the age of onset, and level of hormonal involvement.
Secondary amenorrhoea is where an established menstruation has ceased - for three months in a woman with a history of regular cyclic bleeding, or six months in a woman with a history of irregular periods. This usually happens to woman aged 40-45. Amenorrhoea may cause serious pain in the back near the pelvis and spine. This pain has no cure but can be relieved by doses of progesterone. Progesterone will also help the bleeding or dark colored urine from a woman's vagina.
Hypergonadotropic amenorrhoea refers to conditions with high levels of FSH (and LH). FSH levels are typically in the menopausal range. This implies that the ovary or gonad does not respond to pituitary stimulation. Gonadal dysgenesis or premature menopause are possible causes. Chromosome testing is usually indicated in younger individuals with hypergonadotropic amenorrhoea.
In normogonadotropic amenorrhoea, FSH levels are in the normal range. This would suggest that the hypothalamic-pituitary-ovarian axis is functional. Amenorrhoea may be due to outflow obstruction, or abnormal ovarian regulation or excess androgens as seen in polycystic ovary syndrome.
Cushing's Disease/Syndrome can also cause amenorrhoea due to excessive amounts of cortisol in the blood stream.
A second serious risk factor of amenorrhea is severe bone loss sometimes resulting in osteoporosis and osteopenia. It is the third component of an increasingly common disease known as female athlete triad syndrome. The other two components of this syndrome are osteoporosis and disordered eating. Awareness and intervention can usually prevent this occurrence in most female athletes.
Certain medications, particularly contraceptive medications, can induce amenorrhoea in a healthy woman. The lack of menstruation usually begins shortly after beginning the medication and can take up to a year to resume after stopping a medication. Hormonal contraceptives that contain only progestogen like the oral contraceptive Micronor, and especially higher-dose formulations like the injectable Depo Provera commonly induce this side-effect. Recently, an extended cycle combined oral contraceptive pill which aims to purposefully induce amenorrhea (Lybrel), has been approved by the FDA.
For those who do not plan to have biological children, treatment may be unnecessary if the underlying cause of the amenorrhoea is not threatening to her health.
Unless receiving eggs from an egg donor or in vitro fertilization, a woman is unable to conceive while she is amenorrhoeic. On the other hand, 'athletic' and drug-induced amenorrhoea has no effect on long term fertility as long as menstruation can recommence. The best way to treat 'athletic' amenorrhoea is to decrease the amount and intensity of exercise. Similarly, to treat drug-induced amenorrhoea, stopping the medication on the advice of a doctor is a usual course of action.