Menstruation and Menstrual Disorders: Anovulation. Anovulation can result from disruption at any level in the hypothalamic–pituitary–ovarian (HPO) axis. Consequently, categorizing the different mechanisms of anovulation logically follows a systems approach. A systems approach breaks down the causes of anovulation into four categories: Hypothalamic and brain. Pituitary. Ovarian. Systemic. It is important to remember that anovulation is affected by the health of the entire patient, therefore, some disorders can involve multiple levels of the HPO axis. Anovulation due to disorder of the hypothalamus and brain The hypothalamic causes of anovulation result from decreased or dysfunctional production of Gn. RH. Pharmacological studies have shown Gn. RH release is regulated directly and indirectly by endogenous opioids, catecholamines, and dopamine. Dopamine stimulates the release of Gn. RH, whereas endogenous opioids block dopamine and consequently decrease Gn. RH. In patients with conditions of elevated endogenous opioids, treatment with naloxone blocks opioid receptors and results in a return of LH levels to normal. Corticotropin releasing hormone (CRH) is produced by the hypothalamus and blocks Gn. RH release. CRH is also produced in the amygdala. The central nucleus of the amygdala mediates fear and anxiety by CRH producing neurons. These neurons project to several limbic structures and have been shown to decrease serotonin and increase beta- endorphin production thereby decreasing Gn. RH release. High levels of cortisol from the adrenal glands have also been associated with high levels of CRH implicating stress in anovulation. STRESS INDUCED ANOVULATIONStress has been defined as a state of threatened homeostasis. The stress system is the mechanism by which the body tries to maintain homeostasis. The Ana Lifestyle. Pro ana diet is a very fast and aggressive type of diet to lose weight quickly. The anorexic diet has been gaining a lot of popularity these days.We would like to show you a description here but the site won’t allow us. Nutrition for the Adolescent Female Cross Country Runner by Marie Murphy. Stress includes physical, emotional, and nutritional changes. Reproductive status mirrors the physiologic state and the external environment. ![]() This list presents a sub-set of the Read Code system based on public domain information. It is at present likely to contain some errors and is provided for general. The use of complementary and alternative medicine (CAM) is commonplace in the United States. In a 2002 survey, 36% of Americans used some form of CAM, mostly herbs. Vitamin E is an important vitamin required for the proper function of many organs in the body. It is also an antioxidant. This means it helps to slow down processes. When stress is significant reproductive function decreases in an effort to maintain homeostasis. Stress has also been shown todecrease pregnancy rates and increase miscarriage rates. The stress system is comprised of the hypothalamic–pituitary–adrenal (HPA) axis, arousal, and the autonomic system. The main chemical mediators of stress include CRH, glucocorticoids, and beta- endorphins. CRH has receptors in many different tissues including ovary, endothelium, hypothalamus, and inflammatory tissues. Produced in the hypothalamus, CRH and arginine vasopressin stimulate adrenocorticotropic hormone (ACTH) production in the pituitary. This increases cortisol production in the adrenal glands. Cortisol is a glucocorticoid that acts on multiple body systems and reduces LH, estradiol, and progesterone effects. Many of the effects of glucocorticoids and CRH in a stress response involve systematically inhibiting T helper (Th. Th. 2 shift. 1. 4Beta- endorphins are secreted from nerve terminals in response to CRH and produce the initial euphoria of acute stress, necessary for survival. Dopamine has also been shown to increase during stress in a pattern correlating to cortisol levels. Estrogen has a direct effect on CRH release in stress and promotes CRH synthesis. Elevated levels of CRH and cortisol suppress Gn. RH secretion and consequently decrease ovulation. Stress is a common problem in patients undergoing fertility workup and treatment. Techniques are currently being studied to reduce stress including acupuncture, yoga, and meditation. FUNCTIONAL HYPOTHALAMIC AMENORRHEAFunctional hypothalamic amenorrhea (FHA) is defined as cessation of menses and ovulation without an identifiable organic cause. Examples of organic causes of anovulation include clinical eating disorders and significant weight. FHA therefore is a diagnosis of exclusion with a reported incidence of 1. As further understanding of anovulation develops, the number of patients diagnosed as FHA decreases. Anovulation in FHA results from a decrease in Gn. RH release and consequently decreased gonadotropin release. Such patients also fail to menstruate after treatment with progesterone demonstrating low estrogen levels correlating to chronic lack of gonadotropin stimulation. Slightly increased cortisol levels are typical with low to normal gonadotropins. Such patients do respond to pulsatile Gn. RH treatment further identifying the hypothalamus as the main cause for anovulation. LH pulse frequency is reduced and the interval between pulses is prolonged. One hypothesis for FHA is a synergistic metabolic and psychosocial dysfunction similar to a state of chronic stress. FHA patients have been reported to have a higher likelihood of mood disorders, increased amount of exercise, mild weight loss, and diets with lower fat content, increased fiber, and increased carbohydrates. Personality traits include perfectionism, low self esteem, and poor stress management ability. Another evolving theory is that FHA is a spectrum of reduced gonadotropin secretion due to variable expression of a genetic form of anovulation. This has been seen in males who show reversible hypothalamic hypogonadism and an identifiable genetic mutation (see below). At the present time, similar genes have not been identified in women. This condition represents a state of Gn. RH resistance similar to insulin resistance. Due to the low estrogen and elevated cortisol levels, patients with FHA are at increased risk of bone loss and systemic disease. Treatment should involve nutritional and psychological counseling, however, this form of anovulation often resolves spontaneously. PSYCHOGENIC TRAUMA AND STRESSStudies have shown the impact of external factors in the environment on menstruation and consequently ovulation. Menstrual cycles in college women living together will begin to synchronize. These same women will have longer cycles when spending increasing time with male students. These changes are likely the result of pheromones influencing the hypothalamus. Further studies note the influence of psychological state on menstruation. In patients with clinical depression, cortisol levels were found to be significantly elevated. Other hormones including prolactin, gonadotropins, and estrogen are all normal in patients with psychological distress. When given exogenous Gn. RH, these patients have a normal release of LH and FSH suggesting a suppression of Gn. RH as the cause of anovulation associated with depression. ANOREXIA NERVOSAAnorexia nervosa is an eating disorder stemming from a disordered body image resulting in malnutrition and severe weight loss. The diagnostic criteria includes amenorrhea implying a functional abnormality of the HPO axis. The prevalence is reported to be 0. Complications of anorexia nervosa include a mortality rate of 2–1. Bone density loss occurs as a result of low estrogen levels. Anorexia differs from other forms of psychogenic anovulation. The ovulatory failure in anorexia is due to metabolic changes that occur with weight loss, while the underlying problem is psychological. Gonadotropin levels are reduced in anorexia, as are leptin and estradiol. This hypoestrogenic state results in a thin endometrial lining that does not shed after progesterone treatment. Leptin levels, which correlate with body fat and nutrition status, have been found to play a role in ovulation and are discussed later in this chapter. Triiodothyronine (T3) is decreased and reverse T3 is elevated, resulting in hypothyroid symptoms including dry skin and bradycardia. Growth hormone is also increased due to periods of starvation. Several findings indicate that anovulation associated with anorexia arises at the level of the hypothalamus. The pulse frequency of gonadotropin release is similar to the pulse frequency seen in childhood. Starvation has been shown to decrease Gn. RH release and subsequently decrease gonadotropins. When exogenous Gn. RH is administered in a physiologic pattern the gonadotropin pulse frequency normalizes and ovulation occurs. Levels of CRH are also elevated, correlating with elevated cortisol and suppression of Gn. RH release. 3. 2, 3. Anovulation with anorexia and hypothalamic suppression is not only due to low body fat. Nutritional status and physical activity play a key role in ovulation and treatment. Amenorrhea was noted to occur when weight dropped below 9. In patients who gain appropriate amounts of weight, some remain anovulatory and show decreased gonadotropin levels. Anovulatory anorexics who weighed the same as ovulating anorexics were found to have higher levels of physical activity. Low levels of leptin are also found in patients who have poor eating habits when controlling for weight. As a result, treatment requires nutritional improvement, weight gain, and psychiatric care. This syndrome is serious and carries mortal consequences. BULIMIA NERVOSABulimia nervosa is another eating disorder associated with anovulation. Bulimia nervosa is defined as binge eating with subsequent compensatory behavior (purging) and a poor body image. Unlike anorexia, bulimics are not underweight. Fifty per cent of bulimics have amenorrhea. Bulimics do have decreased levels of LH secretion much like patients with anorexia. Low LH in bulimia is found when body weight is less than 8. Patients with bulimia are not hypoestrogenic and are at less risk for osteoporosis. However, persistently amenorrheic bulimics do have an elevated risk of endometrial cancer due to continuous estrogen stimulation of the uterus. Leptin levels in bulimic patients can be normal, but do decrease with poor nutrition. PHARMACOLOGIC AGENTSEstrogen and progesterone effect gonadotropin release indirectly using biogenic amines as intermediaries. Norepinephrine and epinephrine are responsible for signal transduction between the hypothalamus and the pituitary. These amines increase 2 days prior to the LH surge. Dopamine regulates prolactin and Gn. RH release and is blocked by endogenous opioids. Drugs that affect metabolism and release of these amines will consequently effect changes in the HPO axis. Where to Find A Pro Ana Buddy To Chat About Your Diet.
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