Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0003128 (anovulation)
 1,718 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Over the past 30 years, the number of women participating in organized sports has grown dramatically. Several forms of menstrual irregularities have been described in the female athlete: primary and secondary amenorrhoea, oligomenorrhoea, short luteal phases and anovulation. The incidence of menstrual irregularities is much higher in activities where a thin body is required for better performance. The hormonal pattern seen in these athletes is a hypothalamic amenorrhoea profile. There appears to be a decrease in gonadotrophin-releasing hormone (GnRH) pulses from the hypothalamus, which in turn decreases the pulsatile secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and shuts down stimulation of ovary. Recently, another type of amenorrhoea has been described in swimmers which is characterized by mild hyperandrogenism. Athletes with low weight are at risk of developing the female athletic triad, which includes amenorrhoea, osteoporosis and disordered eating. Athletes with this triad are susceptible to stress fractures. Other issues include the pregnant athlete. Intensive exercise during pregnancy can cause bradycardia. Safe limits of aerobic exercise in pregnancy depend on previous exercise habits. Infertility, which may develop with exercise, is probably reversible with reduction of exercise or weight gain. High impact sports activities may produce urinary incontinence. Oestrogen replacement therapy is often prescribed in amenorrhoeic athletes, but bone loss may not be completely reversible.
 ...
PMID:The female athlete. 1093 9

Polycystic ovary syndrome (PCOS) is the most common cause of menstrual disorders, and is characterized by chronic anovulation, hyperandrogenism and infertility. In recent years, it has become apparent that PCOS is also associated with hyperinsulinemia that is probably central to the pathogenesis of PCOS. As a peculiar vascular pattern has been reported to be present in PCOS, the aim of this study was to investigate intraovarian stromal vascularization in PCOS patients and its possible correlation with sex hormones, gonadotropins and insulin levels. Twenty-eight oligomenorrheic or amenorrheic patients with PCOS and 14 eumenorrheic women with a PCOS-like ovarian pattern undergoing endocrine screening and ultrasound color Doppler intraovarian blood flow were recruited to the study. Ten healthy women with regular menses represented the control group. Hormonal assays (follicle-stimulating hormone (FSH), luteinizing hormone (LH), androstenedione, testosterone, sex hormone-binding globulin (SHBG) and estradiol), oral glucose tolerance test (OGTT), baseline and glucose-induced insulin levels, and transvaginal ultrasonographic and color Doppler analysis (pulsatility index (PI), resistance index (RI) and velocity (Vmax) of ovarian stromal flow) were performed in all participants in the early proliferative phase. Endocrine values showed significant differences in PCOS patients compared with PCOS-like women and controls, while PI and RI indices were significantly higher in controls. PCOS patients were divided into hyperinsulinemic (n = 16) and normoinsulinemic (n = 12). Androstenedione was significantly higher (p < 0.01) in the hyperinsulinemic than in the normoinsulinemic patients and controls, while SHBG was significantly (p < 0.01) lower in the hyperinsulinemic group. Analysis of color Doppler intraovarian vascularization showed a significantly lower RI and a higher Vmax in the hyperinsulinemic subjects than in the normoinsulinemic PCOS patients and controls. An increased stromal blood flow was observed in the PCOS and PCOS-like patients by transvaginal color Doppler evaluation, but this technique is not able to differentiate these two similar ovarian patterns. However, hyperinsulinemic PCOS patients had an increased vascularity of the ovarian stroma. A strong correlation between hyperinsulinemia, hyperandrogenism and low SHBG levels was evidenced, and a hyperinsulinemia-induced mechanism for ovarian stromal angiogenesis is discussed.
 ...
PMID:Polycystic ovary syndrome: relationship between insulin sensitivity, sex hormone levels and ovarian stromal blood flow. 1137 11

To obtain information on the prevalence of anovulation and early menopause and on pituitary-gonadal function among human immunodeficiency virus type 1-infected women, a study was undertaken that used stored serum samples from women aged 20-42 years who participated in selected Adult AIDS Clinical Trials Group protocols. Defined progesterone and follicle-stimulating hormone (FSH) levels were considered presumptive evidence of ovulation and of menopause, respectively. Anovulation occurred in 16 (48%) of 33 women for whom progesterone levels were tested; early menopause occurred in 2 (8%) of 24 women for whom FSH levels were tested. No statistically significant differences were seen in the demographic and clinical characteristics of anovulatory and ovulatory women, although women who ovulated had higher CD4 T cell counts and were less likely to have reported a recent change in menstrual periods. These data support the findings of prior studies of increased frequency of amenorrhea and/or irregular menstrual cycles, particularly among women with lower CD4 T cell counts.
 ...
PMID:Frequency of anovulation and early menopause among women enrolled in selected adult AIDS clinical trials group studies. 1167 23

Polycystic ovary syndrome (PCOS) is a disorder characterized by hyperandrogenism and chronic anovulation. Although the etiology of PCOS is unknown, perturbations of gonadotropin secretion are one of the hallmarks of this disorder. In normal menstrual physiology, the monotropic rise of plasma follicle-stimulating hormone (FSH) during the luteal-follicular transition is critical for follicular development and subsequent ovulation. One of the mechanisms by which FSH is differentially synthesized involves the luteal slowing of gonadotropin-releasing hormone (GnRH) pulse frequency by ovarian steroids. In PCOS, plasma leutinizing hormone (LH) is commonly increased, FSH is typically in the lower follicular range, and LH (and by inference GnRH) pulse frequency is persistently rapid at approximately one LH pulse per hour. The etiology of the neuroendocrine abnormalities in PCOS remain unclear; however, recent studies have revealed decreased sensitivity of the GnRH pulse generator to inhibition by ovarian steroids, particularly progesterone. This abnormality is reversed by the androgen receptor antagonist flutamide, suggesting that elevated androgen levels may alter the sensitivity of the hypothalamic GnRH pulse generator to steroid inhibition and lead to enhanced LH secretion. As such, women with PCOS require higher levels of progesterone to slow the frequency of GnRH pulse secretion, resulting in inadequate FSH synthesis and persistent LH stimulation of ovarian androgens. The decreased sensitivity of the GnRH pulse generator may help to explain the genesis of PCOS during puberty. In normal early puberty, sleep-entrained increases in LH stimulate ovarian steroids, which subsequently suppress LH frequency and amplitude during the subsequent day. In hyperandrogenemic girls destined to develop PCOS, this nocturnal increase in ovarian steroids may not be adequate to suppress the GnRH pulse generator, leading to a persistently rapid LH pulse frequency, impaired FSH production, and inadequate follicular development.
 ...
PMID:Regulation of gonadotropin secretion: implications for polycystic ovary syndrome. 1253 55

Urinary-derived follicle-stimulating hormone (FSH) preparations have been used clinically for many years. Although effective, these have a number of disadvantages, not least of which is their variable composition. The availability of recombinant human FSH (r-hFSH), produced from CHO cells, with its constant composition and exceptionally high purity, has, therefore, aroused great interest. This review focuses on the use of r-hFSH for ovarian stimulation in assisted reproduction technology protocols and the treatment of World Health Organization Group I and II anovulation. The use of r-hFSH has been shown to lead to improvements in efficacy over urinary-derived preparations, particularly in assisted reproductive treatment, and a recent meta-analysis has shown higher ongoing pregnancy rates with the recombinant product. Although the two available recombinant products from CHO cells (follitropin alpha [Gonal-F((R))] and beta [Puregon((R))]) are similar from a physicochemical perspective, some minor advantages have been reported for follitropin alpha in relation to pregnancy rates and better local tolerance to injections. The apparent higher bioactivity of r-hFSH has led to reduced total FSH consumption over shorter treatment periods compared with conventional preparations, thus reducing overall exposure for patients. This is likely to confer not only safety benefits, but also cost-effectiveness as demonstrated through pharmaco-economic modelling.
 ...
PMID:Recombinant human follicle-stimulating hormone: a scientific step to clinical improvement. 1253 25

Polycystic ovarian syndrome (PCOS) is one of the most common endocrine diseases in women. This syndrome is characterized by hyperandrogenism, chronic anovulation, infertility and obesity. The association between PCOS-related hyperandrogenemia and insulin resistance is well documented in the literature. Insulin resistance and the resulting raised plasma levels of insulin are reported to be responsible for the high androgen concentration observed in patients with PCOS. In this prospective study, blood samples for levels of testosterone (T), dehydroepiandrosterone sulfate (DHEAS), luteinizing hormone (LH), follicle-stimulating hormone (FSH), LH/FSH, prolactin and fasting blood sugar (FBS) before starting metformin administration were obtained randomly from 40 women who were apparently obese, had PCOS and had been referred to a university hospital. Metformin was then given at a dose of 500 mg three times a day for 8 weeks, after which time the pretreatment study was repeated. Clinical symptoms of PCOS, including acne and hirsutism score and body mass index (BMI), were assessed before and after the treatment cycle. Metformin therapy resulted in a significant decrease in total testosterone levels and FBS. There was also a significant decline in BMI, length of the menstrual cycle, acne and hirsutism score. There were no significant changes in the levels of DHEAS, prolactin, FSH or LH, or in LH/FSH. The effect of metformin on subjects with elevated DHEAS levels was different to that on individuals with normal DHEAS levels. In the latter group there were only significant improvements in the length of the menstrual cycle, BMI and testosterone and DHEAS levels. It is concluded that metformin therapy in subjects with PCOS results in a decrease in fasting blood sugar and testosterone levels, and leads to a significant improvement in the clinical manifestation of hyperandrogenism. These responses also related to the level of adrenal function.
 ...
PMID:Effects of metformin therapy on hyperandrogenism in women with polycystic ovarian syndrome. 1272 19

Luteinizing hormone (LH) is a crucial physiological regulator of the human menstrual cycle. LH activity is also contained in many medications used to treat anovulation and to stimulate multiple folliculogenesis for assisted reproduction techniques. However, LH activity had previously been regarded as just a contaminant of follicle-stimulating hormone (FSH)-containing products and deemed potentially detrimental for reproductive function. Novel experimental and clinical evidence now suggests that the administration of pharmacological amounts of LH activity, instead of being harmful, is therapeutically advantageous, particularly in the support and modulation of ovarian folliculogenesis. The aim of this article is to provide an overview of the effects of LH activity administration in ovarian stimulation and to outline novel unconventional gonadotropin regimens that might improve the efficacy, safety and convenience of ovulation induction.
 ...
PMID:Current concepts and novel applications of LH activity in ovarian stimulation. 1289 May 91

Women with polycystic ovarian syndrome have chronic anovulation and androgen excess not attributable to another cause. This condition occurs in approximately 4% of women. The fundamental pathophysiologic defect is unknown, but important characteristics include insulin resistance, hyperandrogenism, and altered gonadotropin dynamics. Inadequate follicle-stimulating hormone is hypothesized to be a proximate cause of anovulation. Obesity frequently complicates polycystic ovarian syndrome but is not a defining characteristic. The diagnostic approach should be based largely on history and physical examination, thus avoiding numerous laboratory tests that don't contribute to clinical management. Women with polycystic ovarian syndrome typically present because of irregular bleeding, hirsutism, and/or infertility. These conditions can be treated directly with oral contraceptives, oral contraceptives plus spironolactone, and ovulation induction, respectively. However, women with polycystic ovarian syndrome also have a substantially higher prevalence of diabetes and increased risk factors for cardiovascular disease. They should also be screened, therefore, for these conditions and followed closely if any risk factors are uncovered. For obese women with polycystic ovarian syndrome, behavioral weight management is a central component of the overall treatment strategy.
 ...
PMID:Polycystic ovary syndrome. 1470 63

Human follicle-stimulating hormone (FSH) is now produced in vitro by recombinant DNA technology. FSH being a complex heterodimeric protein, a eukaryotic cell line has been selected for expression work (Chinese hamster ovary cells). The pharmaceutical preparation of recombinant human FSH (r-FSH) differs from that of human menopausal gonadotrophin (HMG) and the first generation of urinary human FSH (u-FSH) in terms of (i) source of bulk materials, (ii) purity and specific activity, (iii) batch to batch consistency, and (iv) complete absence of luteinizing hormone (LH) activity. Pharmacokinetic characterization of r-FSH has shown an absolute bioavailability of approximately 75% after both s.c. and i.m. administration and an apparent terminal half-life of 37 +/- 25 h. These characteristics are very similar to those of u-FSH. Clinical efficacy and safety are currently demonstrated through several randomized, well controlled studies, comparing r-FSH administered s.c. with u-FSH administered i.m. for stimulating follicular development prior to assisted reproduction treatment and in World Health Organization (WHO) group II anovulation. To date, approximately 1000 patients have been treated with r-FSH. Moreover, r-FSH has recently been used successfully in association with recombinant human LH for inducing ovulation and pregnancy in WHO group I anovulatory patients. At this stage of r-FSH preparation assessment, it is likely that r-FSH will replace all urinary-derived FSH preparations for stimulating ovarian follicular development. For clinicians, current experience with r-FSH indicates that it should be used with the regimes and doses applied to u-FSH.
 ...
PMID:Human follicle-stimulating hormone produced by recombinant DNA technology: a review for clinicians. 1572 72

Anovulation is a common cause of female infertility. Treatment for women with anovulation is aimed at induction of ovulation. Ovulation induction with follicle-stimulating hormone (FSH) is indicated in women with WHO type II anovulation in whom treatment with clomifene citrate (clomifene) has failed. The majority of these women have polycystic ovary syndrome. The major disadvantages of ovulation induction with FSH are the risk of ovarian hyperstimulation syndrome and the risk of higher order multiple pregnancies. To reduce the rate of complications due to multiple follicular development, FSH should be administered using a chronic low-dose protocol with small dose increments. In women with WHO type I anovulation, an exogenous supply of luteinizing hormone (LH) is required to achieve an adequate follicular response to FSH treatment. Thus, ovulation induction with FSH is not the treatment of choice in these women. FSH is a hormone that stimulates follicle growth and oocyte maturation. Endogenous FSH is produced by the pituitary gland and exists as a family of isohormones exhibiting distinct oligosaccharide structures. FSH for exogenous administration is derived from urine or is produced as recombinant FSH. The commercially available FSH products all contain different mixtures of FSH isoforms. To determine the effectiveness of urofollitropin (urinary-derived FSH), a comparison with the other available gonadotropins was made (i.e. recombinant FSH and human menopausal gonadotropin). Urofollitropin and recombinant FSH appear to be equally effective and well tolerated for ovulation induction. Human menopausal gonadotropin is comparably effective to urofollitropin in terms of pregnancy outcomes. It remains unclear whether human menopausal gonadotropins have a higher risk of overstimulation and ovarian hyperstimulation syndrome compared to urofollitropin in women with polycystic ovary syndrome. In practice, recombinant products are more convenient to use but are also more expensive. Therefore, if availability is not an issue but costs are, there is still a place for the use of urofollitropins for ovulation induction.
 ...
PMID:Urofollitropin and ovulation induction. 1589 21


<< Previous 1 2 3 4 5 6 7 8 Next >>