Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002453 (amenorrhea)
 6,245 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The median age at menopause in Western populations of women is approximately 51 years. While very late (i.e., after 54 years) menopause is exceedingly uncommon, a sizeable minority of women experience cessation of ovarian function at or prior to age 45. By convention, menopause that occurs at ages 40-45 is considered "early" and occurs in about 5% of women. Premature ovarian failure (POF) is reserved for the approximately 1% of women who experience hypergonadotropic amenorrhea prior to age 40 years. POF represents the end stage of a variety of disorders that result in the loss of ovarian follicles. Depending upon the age at diagnosis, the probability of a genetic, autoimmune, or idiopathic cause will be more or less likely. Two functioning X chromosomes appear necessary for normal ovarian function. The most obvious genetic cause of POF is Turner Syndrome, in which a complete or near-complete loss of the second X chromosome occurs. Turner Syndrome typically results in the most severe and irreversible POF, often clinically evident prior to menarche. Typically, in Turner Syndrome, menopause precedes menarche, and there is no evidence of ovarian function. However, cases with multiple tissues diagnosed as 45, X have been reported to result in ovarian function and even pregnancy. It is likely that mitigating factors, perhaps autosomal, can modify this most severe and irreversible cause of ovarian failure. Lesser degrees of ovarian failure have also been attributed to partial X chromosome deletions and milder degrees of X chromosome mosaicism. Fragile X syndrome is another example of mild POF that can be linked to disorders of the X chromosome. Other genetic defects are believed to cause POF, yet their prevalence has been difficult to determine. The localization of the gene for the blepharophimosis/ptosis/POF Syndrome has been recently reported, yet this finding has not been seen commonly in POF. Other genetic syndromes including POF await elucidation. Many transgenic "knock-out" animals have been created with deficient ovarian function. Most interesting along these lines is the heterozygous FSH receptor knock-out, which exhibits a reduced follicle reserve and early ovarian depletion. Application of this knowledge and translation of these transgenic experiments into elucidation of clinical disease has been difficult, but represents an area of tremendous potential progress in the understanding of the pathogenesis of POF. Another approach to the genetics of POF has been to examine the genome of affected and unaffected individuals. The genetics appear to differ greatly depending upon the timing of the expression of the POF. For example, women with early menopause are more likely to possess the PVUII polymorphic allele for estrogen receptor alpha. Whether or not this polymorph is more common in women with earlier menopause, i.e., POF, is unclear. Pedigree data indicate that early menopause and premature menopause sort similarly within families. The only difference between women with true POF and those with early menopause may be in the timing of the expression of the syndrome, and not in the genetics. Population genetic approaches analyzing affected and unaffected individuals are underway in several research centers and represent another area of progress. Immune and other, idiopathic causes of POF await further clarification. It is clear that this is an area of great research potential. Understanding how ovaries fail may assist women with this disorder by facilitating the development of novel therapies. Additionally, such information will provide important clues about optimizing ovarian function in individuals without POF who are seeking extension of their reproductive life spans or fertility enhancement by other means.
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PMID:Mechanisms of premature ovarian failure. 1277 39

In adolescent girls, amenorrhea is sometimes viewed as a variant of normal; in fact, however, during the first gynecologic year, the 95th percentile for cycle length is 90 days. Although early menstrual cycles are frequently anovulatory and may be somewhat irregular, girls with menses coming less frequently than every 90 days may have significant pathology associated with hypoestrogenism. Hypoestrogenism is a known risk factor for the development of osteoporosis. Causes of oligomenorrhea and amenorrhea include the relatively common conditions of hyperandrogenism, eating disorders, and exercise-induced amenorrhea, as well as uncommon conditions such as pituitary tumor, gonadal dysgenesis, and premature ovarian failure. Even functional hypothalamic oligomenorrhea has been linked to reduced bone density. Attention to menstrual irregularity and the earlier diagnosis of conditions causing it may lead to interventions that will benefit life-long bone health.
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PMID:Adolescent girls, the menstrual cycle, and bone health. 1279 70

Premature Ovarian Failure is a heterogeneous disorder with numerous causes. The exact prevalence of POF is unknown. In this study, we want to make Differentiate diagnosis of hypergonadotropic amenorrhea and to determine the difference between them. Retrospective, we follow up 475 women at which we perform ovarian stimulation and we observe that 6 (1.3%) have Gonadotropin resistant ovary syndrome in IVF-centre--MU--Varna.
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PMID:[Diagnostic and clinical status of premature ovarian failure]. 1457 66

Both oral and intravenous high-dose cyclophosphamide (CYC) regimens are associated with serious side effects when used for the treatment of systemic sclerosis (SSc). The aim of the present trial was to test the safety of low-dose intravenous CYC in patients with SSc. Eight SSc patients, in whom CYC treatment was warranted, were studied at baseline and after 6 months' intravenous CYC treatment (500 mg pulses at weeks 0, 1, 2, 6, 10, 14, 18 and 22). Side effects probably related to CYC treatment were carefully investigated. The development of amenorrhea was assessed during the period of treatment and over the following 12 months. The therapy was well tolerated overall. No patient discontinued treatment because of side effects. Leukopenia, premature ovarian failure, hemorrhagic cystitis, microscopic hematuria and liver toxicity were never detected. The most common adverse events were mild and self-limiting nausea and weakness. Our data suggest that low-dose intravenous CYC is relatively safe, at least in the short term. Further studies are needed to assess both the efficacy and the long-term safety.
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PMID:Low-dose intravenous cyclophosphamide in systemic sclerosis: a preliminary safety study. 1467 13

Follistatin plays an important role in female physiology by regulating FSH levels through blocking activin actions. Failure to regulate FSH has been implicated as a potential cause of premature ovarian failure. Premature ovarian failure is characterized by amenorrhea, infertility, and elevated gonadotropin levels in women under the age of 40. Because follistatin is essential for postnatal viability, we designed a cre/loxP conditional knockout system to render the follistatin gene null specifically in the granulosa cells of the postnatal ovary using Amhr2cre transgenic mice. The follistatin conditional knockout females develop fertility defects, including reduced litter number and litter sizes and, in the most severe case, infertility. Reduced numbers of ovarian follicles, ovulation and fertilization defects, elevated levels of serum FSH and LH, and reduced levels of testosterone were observed in these mice. These findings demonstrate that compromising granulosa cell follistatin function leads to findings similar to those characterized in premature ovarian failure. Follistatin conditional knockouts may therefore be a useful model with which to further study this human syndrome. These studies are the first report of a granulosa cell-specific deletion of a gene in the postnatal ovary and have important implications for future endeavors to generate ovary-specific knockout mouse models.
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PMID:Granulosa cell-specific inactivation of follistatin causes female fertility defects. 1470 41

Premature ovarian failure (POF) is generally defined as amenorrhea, hypoestrogenism, and elevated gonadotropins occurring in a woman before the age of 40 yr. Usually, the etiology is unknown. Turner syndrome (TS, monosomy X), also associated with ovarian failure, has a characteristic neurocognitive profile. TS females, as a group, have specific deficits in visual-spatial abilities, visual-perceptual abilities, motor function, nonverbal memory, executive function, and attentional abilities. Observed deficits in TS could be due to endocrine (estrogen deficiency) or genetic factors. If early estrogen deficiency contributes to the cognitive deficits in TS, women with POF would also be at risk for similar findings. The objective of this work was to examine the specific cognitive profile in women with POF and compare it with women with TS and normal female controls. We compared two unique populations (women with POF vs. TS), both with earlier estrogen deficiency. The TS group only had a major genetic deficiency, absence of all or part of one X chromosome. We evaluated the cognitive performance of estrogen-repleted women with POF (n = 89), compared with verbal IQ- and socioeconomic status-matched females with TS (n = 94) and controls (n = 96). Performance by the POF population was similar to that of controls and differed from the TS population. In contrast, TS adults had relative difficulty with measures of spatial/perceptual skills, visual-motor integration, affect recognition, visual memory, attention, and executive function. These deficits are apparent in TS women, despite apparently adequate estrogen treatment. The cognitive phenotypes of women with POF and normal controls are similar and differ from women with TS, indicating that prior estrogen deficiency does not have a major impact on cognitive function in adult females. The genetic deficiencies of women with TS most likely account for their specific cognitive phenotype.
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PMID:The effect of genetic differences and ovarian failure: intact cognitive function in adult women with premature ovarian failure versus turner syndrome. 1507 Sep 50

BACKGROUND: Premature Ovarian Failure (POF), defined as the development of hypergonadotropic amenorrhea before the age of 40 years, occurs in about 1% of all women. Other than karyotype abnormalities, very few genes are known to be associated with this ovarian dysfunction. Recently, in seven patients who presented with POF and white matter abnormalities on MRI (ovarioleukodystrophy) eight mutationswere found in EIF2B2, 4 and 5. METHODS: To further test the involvement of known mutations of EIF2B genes in POF, we screened 93 patients with POF who did not have identified leukodystrophy or neurological symptoms. We evaluated these eight mutations and two additional mutations that had been found in patients with milder forms of eIF2B-related disorders. We used restriction enzymes and direct sequencing. RESULTS: None of the known mutations in EIF2B genes, either homozygous or heterozygous, were identified in our 93 patients with pure 46,XX POF. The upper 95 % confidence limit of the proportion 0/93 is 3.2%. CONCLUSIONS: We conclude that eIF2B mutations, already described in cases of POF associated with white matter abnormalities, are an uncommon cause of pure spontaneous premature ovarian failure.
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PMID:Screening for known mutations in EIF2B genes in a large panel of patients with premature ovarian failure. 1550 43

We report a case of pelvic organ prolapse quantification (POPQ) stage III uterine prolapse in a 25-year-old nulligravida. Premature ovarian failure was diagnosed after 1 year of amenorrhea. Localized scleroderma was noticed on her thigh and lower back. We discuss the possible role of scleroderma and ovarian failure on the occurrence of uterine prolapse in light of the literature.
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PMID:Uterine prolapse in a young nulligravida with scleroderma and premature ovarian failure. 1565

The adolescent is an important period in which the peak bone mass is acquired. A sufficient attainment of peak bone mass is important as well as a prevention of bone loss in postmenopausal period in order to prevent osteoporosis in future. It is well known that the estrogen deficiency is at risk of developing osteopenia. Anorexia nervosa, excessive exercises, Turner's syndrome and premature ovarian failure are leading causes of prolonged amenorrhea in young women. However, estrogen deficiency is not the only cause of low bone mass in these women. Although hormone replacement therapy is effective to increase bone mineral density in these women, management of amenorrhea should be individualized according to the status of bone metabolism.
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PMID:[Amenorrhea in young women]. 1577 29

Thanks to improvements in treatment regimens, more and more patients are now surviving cancer. However, cancer survivors are faced with the serious long-term effects of the different modalities of cancer treatments. One of these adverse effects is chemotherapy-induced irreversible damage to the ovarian tissues, which leads to premature ovarian failure and its resulting consequences such as hot flashes, osteoporosis, sexual dysfunction and the risk of infertility. Chemotherapy-induced ovarian failure (or chemotherapy-induced premature menopause) affects the quality of life of female cancer survivors. Although there is no clear definition of chemotherapy-induced ovarian failure, irreversible amenorrhoea lasting for several months (>12 months) following chemotherapy and a follicle stimulating hormone level of > or = 30 MIU/mL in the presence of a negative pregnancy test seems to be an appropriate characterisation. Different chemotherapy agents, alkylating cytotoxics in particular, have the potential to cause progressive and irreversible damage to the ovaries. The result of this damage is a state of premature ovarian failure, with progressive declining of estrogen levels, decreasing bone mass and an increased risk of fractures. Historically, hormonal replacement therapy (HRT) has been used to treat menopausal problems in the general population, but concerns about the potential of estrogen to increase the risk of breast cancer in women at high-risk or increase the risk of recurrence in cancer survivors, have forced physicians to utilise alternative treatments. This review discusses some of the newer therapies that are now available to provide appropriate symptom control, avoid complications such as fractures and possibly prevent infertility by making the ovarian epithelium less susceptible to cytotoxic agents.
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PMID:Chemotherapy-induced ovarian failure: manifestations and management. 1585 42


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