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Query: UMLS:C0028754 (obesity)
 124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Polycystic ovary syndrome (PCOS) is the most common disorder of ovarian function in premenopausal women. PCOS is characterised by chronic anovulation and androgen excess with clinical manifestation of irregular menstrual cycles, hirsutism and/or acne. Insulin resistance with resultant hyperinsulinaemia, irrespective of excess weight or frank obesity, has been reported in patients with PCOS, and, as insulin has a direct effect on ovarian androgen production in vitro, insulin resistance may play a crucial role in the physiopathology of PCOS. Although the molecular mechanism(s) of insulin resistance in PCOS is unclear, excessive insulin-independent serine phosphorylation of the beta subunit of the insulin receptor, as reported in some patients with PCOS, has been put forward as a new mechanism for insulin resistance. Insulin-sensitising agents have recently been investigated for their role in the short term treatment of insulin resistance in PCOS. Controlled studies have shown that metformin administration, by promoting bodyweight loss, can decrease fasting and stimulated plasma insulin levels. However, other studies have shown metformin 500 mg 3 times daily to decrease insulin secretion and to reduce ovarian production of 17alpha-hydroxyprogesterone with recovery of spontaneous or clomifene-induced ovulation, independently of weight loss. These findings suggest a new indication for metformin and present insulin-sensitising agents as a novel approach in the treatment of ovarian hyperandrogenism and abnormal ovulation in PCOS. They also suggest that long term administration of metformin might be helpful in treating insulin resistance, thus reducing risks of type 2 (non-insulin-dependent) diabetes and cardiovascular disease in these patients.
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PMID:Insulin resistance, polycystic ovary syndrome and metformin. 1057 24

Obesity, ultrasonic ovarian morphology, serum LH levels and LH/FSH ratio are inconstant symptoms of the polycystic ovary syndrome (PCOS) and are thus no longer essential for diagnosis. PCOS is diagnosed today by the finding of chronic anovulation and hyperandrogenism characterized by a high serum level of "free" testoterone. The other causes of hyperandrogenism, as well as anovulations due to hyperprolactinemia, high levels of FSH and abnormal thyroid function have to be ruled out. PCOS is very often associated with insulin resistance (IR) and hyperinsulinemia (hyper I). From in vitro and vivo studies and treatment of hyper I, it has been shown that the hyper I of PCOS stimulates androgen production. Hyper I of PCOS increases the activity of androgens: by first provoking an important decrease of the sex hormone binding globulin (SHBG) thus increasing the "free", bioactive testosterone level. and then by activating the cytochrome P 450 c 17 alpha enzymatic system that controls androgen production. Subsequent to metformin administration, the reduction of hyper I and androgen serum levels creates a favorable condition for the resumption of ovarian function and clomiphene citrate action. This explains the high percentage of ovulations and pregnancies.
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PMID:[Diagnosis and treatment of polycystic ovary syndrome]. 1059 43

We have previously demonstrated that obese hyperandrogenic amenorrheic women are less likely to ovulate after clomiphene citrate (CC) medication. The present study was designed to identify whether additional endocrine screening characteristics, all potentially involved in ovarian dysfunction in 182 normogonadotropic oligoamenorrheic infertile women, are associated with ovarian response, which may improve overall prediction of CC-resistant anovulation. Standardized endocrine screening took place before initiation of CC medication (50 mg/day; increasing doses up to 150 mg/day if required) from cycle days 3-7. Screening included serum assays for fasting insulin and glucose, insulin-like growth factor I (IGF-I), IGF-binding protein-1 (IGFBP-1), IGFBP-3, free IGF-I, inhibin B, leptin, and vascular endothelial growth factor. Forty-two women (22% of the total group) did not ovulate at the end of follow-up (a total number of 325 cycles were analyzed). Fasting serum insulin, insulin/glucose ratio, IGFBP-1, and leptin were all significantly different in univariate analyses (P < or = 0.02), comparing CC responders vs. nonresponders. Forward stepwise multivariate analyses in combination with factors reported earlier for prediction of patients remaining anovulatory after CC revealed a prediction model including 1) free androgen index (FAI = testosterone/sex hormone-binding globulin ratio), 2) cycle history (oligomenorrhea or amenorrhea), 3) leptin level, and 4) mean ovarian volume. These data suggest that decreased insulin sensitivity, hyperandrogenemia, and obesity, all associated with polycystic ovary syndrome, are prominent factors involved in ovarian dysfunction, preventing these ovaries from responding to stimulation by raised endogenous FSH levels due to CC medication. By using leptin instead of body mass index or waist to hip ratio, the previous model for prediction of patients remaining anovulatory after CC medication could be slightly improved (area under the curve from 0.82-0.85). This may indicate that leptin is more directly involved in ovarian dysfunction in these patients. The capability of insulin and IGFBP-1 to predict patients who remain anovulatory after CC disappears when FAI enters into the model due to a significant correlation between FAI and these endocrine parameters. This suggests that markers for insulin sensitivity (e.g. IGFBP-1 and insulin) are associated with abnormal ovarian function through its correlation with androgens, whereas leptin is directly involved in ovarian dysfunction.
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PMID:Free androgen index and leptin are the most prominent endocrine predictors of ovarian response during clomiphene citrate induction of ovulation in normogonadotropic oligoamenorrheic infertility. 1069 Aug 75

A special herbal tea has been used to treat clomiphene-resistant anovulatory disease and obesity effectively, especially in polycystic ovary syndrome (PCOS) cases with hyperinsulinemia. The effect of the herbal tea on obesity and anovulation was investigated in androgen-sterilized rats (ASR). The ASR model was established by subcutaneous injection of 1.25 mg testosterone propionate to Sprague-Dawley female rats at the age of 9 days. Rats were sacrificed around 112 days of age. ASR manifested with PCO, anovulation, high food intake, elevated body weight, and obesity. Immunocytochemistry demonstrated that estrogen receptors (ER) were predominantly distributed in the cytoplasm of neuropeptide Y (NPY)-containing neurons in the preoptic area (POA), and the coexpression was also found in the nuclei and fibers of NPY-synthesizing neurons in the arcuate nucleus (ARC). Compared with that in normal control rats, NPY expression was increased, the numbers of ER in hypothalamic ARC-median eminence (ME) decreased, gonadotropin-releasing hormone (GnRH) levels in ME was decreased, serum estrogen (E2) and leptin were elevated, and follicular stimulating hormone (FSH) and luteinizing hormone (LH) levels were reduced significantly in ASR. Significantly negative correlations between NPY and ER or GnRH, and between leptin and FSH or LH were observed. A positive correlation existed between serum leptin and body weight. These metabolic-endocrine changes in ASR were normalized after feeding the herbal tea. Both obesity and hypogonadotropin were expressed in ASR. The abnormal ovarian hormone milieu (elevated E2 levels) may have enhanced NPY expression and resulted in less GnRH and gonadotropin secretion. The herbal tea reduced body weight and induced ovulation in ASR.
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PMID:The effect of a special herbal tea on obesity and anovulation in androgen-sterilized rats. 1071 43

Therapeutic approaches to chronic anovulation from polycystic ovaries in clomiphene-resistant infertile patients are under debate. This study discusses evidence that supports the possible predictive value of serum basal level of androstenedione in the choice of the better therapy between laparoscopic ovarian electrocautery and ovulation induction. Lower androstenedione levels seem to be correlated with a better ovarian response after ovulation induction with gonadotropins, while high androstenedione levels are associated with a higher incidence of conception after laparoscopic ovarian electrocautery. Obesity does not seem to represent a hindrance to laparoscopic treatment.
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PMID:Predictive value of serum androstenedione basal levels on the choice of gonadotropin or laparoscopic ovarian electrocautery as ovulation induction in clomiphene citrate-resistant patients with polycystic ovary syndrome. 1081 6

Recent diagnostic and pharmacologic developments have focused renewed attention on polycystic ovary syndrome. Clinical features of the syndrome include anovulation, hyperandrogenism and menstrual dysfunction, but several other abnormalities, including hyperinsulinemia, luteinizing hormone hypersecretion, elevated testosterone levels and acyclic estrogen production, have been documented. Accompanying obesity and lipid abnormalities compound the risk of developing diabetes mellitus or cardiovascular disease, and chronic anovulation increases the risk for endometrial cancer. A careful history and physical examination should guide diagnostic testing. Slowly progressive hyperandrogenic symptoms with anovulation of peripubertal onset often represent polycystic ovary syndrome. Treatment goals include symptom management and the identification and prevention of potential cardiovascular risks. Treatment should take into account the patient's desire for fertility. Advances in transvaginal ultrasonography and infertility treatments, including newer medications, have facilitated assisted reproduction in patients with polycystic ovary syndrome. Ongoing pharmacologic research focusing on the treatment of insulin resistance appears promising in reversing the longterm complications of the syndrome.
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PMID:Polycystic ovary syndrome: it's not just infertility. 1099 32

Obesity is a major feature in women with polycystic ovary syndrome (PCOS), and evidence suggests that obesity contributes to the pathogenesis of PCOS by aggravating the intrinsic insulin resistance of these women. Hyperinsulinemia appears to increase circulating androgens in PCOS by stimulating ovarian androgen production and suppressing serum SHBG, and also appears to play a pathogenic role in the anovulation of the disorder. The use of insulin sensitizing drugs has been shown to decrease serum insulin in both obese and nonobese women with PCOS, and to simultaneously reduce circulating ovarian androgens and to improve ovulation.
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PMID:Obesity, insulin, sex steroids and ovulation. 1099 13

Estrogen replacement therapy (ERT) increases a woman's risk of developing endometrial cancer approximately 120% for each 5 years of use. ERT increases a woman's risk of developing breast cancer approximately 10% for each 5 years of use. To reduce the greatly increased endometrial cancer risk, progestins have been added to ERT (estrogen-progestin replacement therapy; EPRT) for between 5 and 15 days (usually 7 or 10 days) per month in a sequential fashion (sequential EPRT; SEPRT) or with each dose of ERT (continuous-combined EPRT; CEPRT). We conducted two large case-control studies in postmenopausal women in Los Angeles to evaluate the effects of these changes on endometrial and breast cancer risks. As expected CEPRT was not associated with any increased risk of endometrial cancer. SEPRT with the progestin being given for 10 days per month also did not increase endometrial cancer risk. SEPRT with the progestin being given for 7 days per month did increase endometrial cancer risk with only a relatively slight reduction in risk compared to ERT effectively proportional to the reduction in the number of days of unopposed estrogen. The sharp contrast between the effects of 7 days and 10 days of progestin in SEPRT suggests that the extent of endometrial sloughing or of 'terminal' differentiation at the completion of the progestin phase may play a critical role in determining endometrial cancer risk. This may provide an explanation of why endometrial cancer risk increases so sharply with age in young women even in countries where obesity-associated anovulation is very uncommon; extended periods of unopposed estrogen is not an explanation but less than 10 days of an 'adequate' progesterone level may be. EPRT significantly increased the risk of breast cancer. EPRT was associated with an approximately 24% increase in risk for each 5 years of use; the effect was some 212-fold greater than the effect of ERT, which we had previously predicted on theoretical grounds. This effect could also be predicted from the results on mammographic densities seen in the PEPI randomized trial of different forms of hormone replacement therapy (HRT). In the PEPI trial EPRT increased mammographic densities to a much greater extent than ERT. Progestins need to be given to protect the endometrium. They need to be delivered to the endometrium in a manner that will have the least effect on the breast. This can be carried out by using a vaginal or direct endometrial route of administration. The vaginal route will provide adequate endometrial progestin levels with low blood levels so that the effects of the progestin on the breast should be small; with the direct endometrial route the blood progestin levels are even lower, and the effects of the progestin on the breast will be effectively zero. If this is unacceptable to a woman, then giving progestins by mouth (or transdermally) for 10 days every 3 to 4 months should provide satisfactory protection of the endometrium when used with standard-dose conjugated estrogen (CE). This regimen has much less effect on the breast than monthly SEPRT or CEPRT. Two clinical trials of 10 mg per day of MPA for 14 days every 3 months and 0.625 mg/day of CE have been published. Both studies suggest that this approach may be satisfactory in that the extent of hyperplasia was minimal. More studies of this approach are urgently needed.
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PMID:Progestins and menopause: epidemiological studies of risks of endometrial and breast cancer. 1110 73

An established fact in the polycystic ovarian syndrome (POS) is an abnormal ovarian steroidogenesis. Though this suggest an intrinsic ovarian defect, the syndrome could also be influenced by factors outside the ovaries. Although of unknown etiology, the POS is one of the most frequent endocrine disorders in the gynecologic practice. The disorder is characterized by ultrasound findings of enlarged polycystic ovaries, hyperandrogenism, menstrual disorders, obesity and including the appearance of infertility. There are a series of mechanisms involved in the extraovarian androgen increase in patients with POS. Among these mechanisms are implicated those of central and peripheral origin, genetic factors and adrenocortical dysfunction. In the same way, the alterations produced could imply genetic, molecular biological, biochemical, physiological and endocrinological factors. Sometimes all these factors could interact at the same time. The high serum androgen level could stop the pituitary gonadotropin production, either as a direct mechanism or as a result of its peripheral conversion. The increased androgens also explain the manifestations of clinical acne, hirsutism, and the detention in follicular ovarian maturation. All these manifestations are related with the menstrual disorders, anovulation, and infertility that these patients develop. The characteristics of the extraovarian POS include the 17-hydroxyprogesterone elevation in response to the ACTH test and the dexamethasone suppression of adrenal androgens. It is possible to improve the ovarian function in some patients with POS. This could be achieved with clomiphene citrate associated with glucocorticoids to induce ovulation.
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PMID:[Polycystic ovary syndrome of extra-ovarian origin. Review]. 1129 32

Polycystic ovary syndrome (PCOS) is classically characterised by ovarian dysfunction (oligomenorrhoea, anovulation and infertility), androgen excess (hirsutism and acne), obesity, and morphological abnormalities of the ovaries (cystic enlargement and stromal expansion). More recently, insulin resistance has been found to be common in PCOS, along with an increased prevalence of other features of the "metabolic syndrome", namely glucose intolerance, type 2 diabetes mellitus, and hyperlipidaemia. Hyperinsulinaemia is likely to contribute to the disordered ovarian function and androgen excess of PCOS. Reducing insulin resistance by lifestyle modifications such as diet and exercise improves endocrine and menstrual function in PCOS. These lifestyle modifications are the best initial means of improving insulin resistance. Metformin, an oral hypoglycaemic agent that increases insulin sensitivity, has been shown to reduce serum concentrations of insulin and androgens, to reduce hirsutism, and to improve ovulation rates. The effect of metformin alone on fertility rates is unknown. Some studies suggest that metformin will reduce total body weight to a small extent, but with a predominant effect on visceral adipose reduction. The effects of metformin on lipid abnormalities, hypertension or premature vascular disease are unknown, but the relative safety, moderate cost, and efficacy in reducing insulin resistance suggest that metformin may prove to be of benefit in combating these components of the "metabolic" syndrome in PCOS. Further properly planned randomised controlled trials are required.
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PMID:Metformin and intervention in polycystic ovary syndrome. Endocrine Society of Australia, the Australian Diabetes Society and the Australian Paediatric Endocrine Group. 1145 23


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