Eating Disorder leading to Amenorrhoea

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.

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 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.Female athletes or women who perform considerable amounts of exercise on a regular basis are at risk of developing ‘athletic’ amenorrhoea. It was thought for many years 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. However recent studies have shown that there are no differences in the body composition, or hormonal levels in amenorrheic athletes. Instead, amenorrhea has been shown to be directly attributable to a low energy availability. Many women who exercise at a high level do not take in enough calories to expend on their exercise as well as to maintain their normal menstrual cycles.