Amenorrhoea
From Wikipedia, the free encyclopedia
| ICD-10 | N91 |
|---|---|
| ICD-9 | 626.0 |
Amenorrhoea (BE) or amenorrhea (AmE) 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.
Female athletes or women who perform considerable amounts of exercise on a regular basis are at risk of developing 'athletic' amenorrhea. It is suspected that low body fat levels and exercise related chemicals (such as beta endorphins and catecholamines) disrupt the interplay of the sex hormones estrogen and progesterone.
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.
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[edit] Etymology and definition
The term is derived from Greek: a = negative, men = month, rhoia = flow. Derived adjectives are amenorrhoeal and amenorrheic. The opposite is the normal menstrual period.
There are two types of amenorrhoea, primary and secondary amenorrhoea. Primary amenorrhoea is the absence of menstruation in a woman by the age of 16. Also, as pubertal changes precede the first period, menarche, women who have no sign of thelarche or pubarche and thus are without evidence of initiation of puberty by the age of 14 have primary amenorrhoea. (Reference: Speroff L et al, Clinical Gynecologic Endocrinology and Infertility, 1999)
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.
[edit] Overview
Amenorrhoea is a symptom with many potential causes. Primary amenorrhoea 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 is often caused by hormonal disturbances from the hypothalamus and the pituitary gland or from premature menopause, or intrauterine scar formation.
[edit] Classification
Hypogonadotropic amenorrhoea refers to conditions where there are very low levels of serum FSH and LH. Generally, inadequate levels of these hormones lead to inadequately stimulated ovaries who then fail to produce enough estrogen to stimulate the endometrium (uterine lining), hence amenorrhoea. This is typical for conditions of pubertal delay, hypothalamic or pituitary dysfunction. In general, women with hypogonadotropic amenorrhoea are potentially fertile.
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 amenorrhea, FSH levels are in the nomal range. This would suggest that the hypothalamic-pituitary-ovarian axis is functional. Amenorrhea may be due to outflow obstruction, or abnormal ovarian regulation or excess androgens as seen in polycystic ovary syndrome.
[edit] Causes
[edit] Primary amenorrhoea
- Gonadal dysgenesis, including Turner Syndrome.
- Mullerian agenesis (Muller-Rokitansky-Kustner-Hauser syndrome (MRKH)).
- Androgen insensitivity syndrome.
- Delay in hypothalamic-pituitary maturation.
- Olfacto-genital dysplasia, Kallmann syndrome.
- Vaginal obstruction, cryptomenorrhea.
- Receptor abnormalities for FSH, LH.
- Specific forms of congenital adrenal hyperplasia
- Swyer syndrome.
- Galactosemia.
- Aromatase deficiency
- Prader-Willi syndrome
- Papaya consumption
[edit] Secondary amenorrhoea
- Pregnancy
- Anovulation
- Menopause
- Premature menopause
- Hypothalamic-pituitary dysfunction, including
- Exercise amenorrhoea, related to excessive physical exercise
- Stress amenorrhoea,
- Eating disorders and weight loss, (including anorexia nervosa)
- Hyperprolactinemia (elevated prolactin levels)
- Polycystic ovary syndrome (PCO-S)
- Androgen producing tumor (i.e arrhenoblastoma)
- Intrauterine adhesions (Asherman's Syndrome)
- Thyroid dysfunction
- Hemochromatosis
HIGH RISK SPORTS:
- Ballet
- Track and Field
- Swimming
- Cycling
- Gymnastics
- all other intense and strenuous sports
[edit] Treatments
Treatments vary based on the underlying condition. Key issues are problems of surgical correction if appropriate, estrogen therapy (if estrogen levels are low), and fertility.
For those who do not plan to have biological children, treatment may be unnecessary if the underlying cause of the amenorrhea is not threatening to her health.
A woman is unable to conceive whilst she is amenorrhoeic, but 'athletic' amenorrhoea has no effect on long term fertility once menstruation recommences. The best way to treat 'athletic' amenorrhoea would be to decrease the amount of, and the intensity of exercise.
[edit] History
Historically, the term amenorrhoea has often been used as a euphemism for "unwanted pregnancy" and many folk treatments for this condition are in fact abortifacients. Pregnancy, as noted, is only one potential cause for amenorrhea; sometimes pseudo-pregnancy can be a cause for this as well.
