Pituitary-ovarian relationships in polycystic ovary syndrome

Developmental programming of the neuroendocrine axis by steroid hormones: Insights from the sheep model of PCOS

The reproductive neuroendocrine system is a key target for the developmental programming effects of steroid hormones during early life. While gonadal steroids play an important role in controlling the physiological development of the neuroendocrine axis, human fetuses are susceptible to adverse programming due to exposure to endocrine disrupting chemicals with steroidal activity, inadvertent use of contraceptive pills during pregnancy, as well as from disease states that result in abnormal steroid production. Animal models provide an unparalleled resource to understand the effects of steroid hormones on the development of the neuroendocrine axis and their role on the developmental origins of health and disease. In female sheep, exposure to testosterone (T) excess during fetal development results in an array of reproductive disorders that recapitulate those seen in women with polycystic ovary syndrome (PCOS), including disrupted neuroendocrine feedback mechanisms, increased pituitary responsiveness to gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) hypersecretion, functional hyperandrogenism, multifollicular ovarian morphology, and premature reproductive failure. Similar to a large proportion of women with PCOS, these prenatally T-treated sheep also manifest insulin resistance and cardiovascular alterations, including hypertension. This review article focuses on the effects of prenatal androgens on the developmental programming of hypothalamic and pituitary alterations in the sheep model of PCOS phenotype, centering specifically on key neurons, neuropeptides, and regulatory pathways controlling GnRH and LH secretion. Insights obtained from the sheep model as well as other animal models of perinatal androgen excess can have important translational relevance to treat and prevent neuroendocrine dysfunction in women with PCOS and other fertility disorders.

Deconstructing a Syndrome: Genomic Insights Into PCOS Causal Mechanisms and Classification

Polycystic ovary syndrome (PCOS) is among the most common disorders in women of reproductive age, affecting up to 15% worldwide, depending on the diagnostic criteria. PCOS is characterized by a constellation of interrelated reproductive abnormalities, including disordered gonadotropin secretion, increased androgen production, chronic anovulation, and polycystic ovarian morphology. It is frequently associated with insulin resistance and obesity. These reproductive and metabolic derangements cause major morbidities across the lifespan, including anovulatory infertility and type 2 diabetes (T2D). Despite decades of investigative effort, the etiology of PCOS remains unknown. Familial clustering of PCOS cases has indicated a genetic contribution to PCOS. There are rare Mendelian forms of PCOS associated with extreme phenotypes, but PCOS typically follows a non-Mendelian pattern of inheritance consistent with a complex genetic architecture, analogous to T2D and obesity, that reflects the interaction of susceptibility genes and environmental factors. Genomic studies of PCOS have provided important insights into disease pathways and have indicated that current diagnostic criteria do not capture underlying differences in biology associated with different forms of PCOS. We provide a state-of-the-science review of genetic analyses of PCOS, including an overview of genomic methodologies aimed at a general audience of non-geneticists and clinicians. Applications in PCOS will be discussed, including strengths and limitations of each study. The contributions of environmental factors, including developmental origins, will be reviewed. Insights into the pathogenesis and genetic architecture of PCOS will be summarized. Future directions for PCOS genetic studies will be outlined.

Acute progesterone feedback on gonadotropin secretion is not demonstrably altered in estradiol-pretreated women with polycystic ovary syndrome

Women with polycystic ovary syndrome (PCOS) demonstrate gonadotropin-releasing hormone (GnRH) pulse generator resistance to suppression with 7 days of progesterone and estradiol administration. It remains unknown whether such women demonstrate impairments in acute progesterone negative feedback on LH pulse frequency or progesterone positive feedback on gonadotropin release. This was a randomized, double-blind, placebo-controlled crossover study designed to test the hypothesis that acute, progesterone-related suppression of LH pulse frequency and progesterone-related augmentation of gonadotropin release are impaired in PCOS. Twelve normally cycling women and 12 women with PCOS completed study. Volunteers were pretreated with transdermal estradiol (0.2 mg/day) for 3 days and then underwent a frequent blood sampling study (20:00-20:00 h), during which they received micronized progesterone (100 mg) or placebo at 06:00 h. In a second study admission, volunteers received the intervention they did not receive during the first admission, but the protocol was otherwise identical. The primary outcome measures were LH secretory characteristics and circulating gonadotropin concentrations. Exogenous progesterone did not reduce LH pulse frequency in either group. Mean LH, pulsatile LH secretion, LH pulse mass, and mean FSH increased more with progesterone compared to placebo in both groups. Although trends toward less pronounced changes in LH pulse mass and pulsatile LH secretion were observed in the PCOS group, these differences were not statistically significant. In summary, exogenous progesterone did not suppress LH pulse frequency within 12 hours in estradiol-pretreated women, and the positive feedback effect of progesterone on gonadotropin release was not demonstrably impaired in PCOS. NEW & NOTEWORTHY: This study indicated that exogenous progesterone does not reduce LH pulse frequency within 12 h in women with PCOS, but progesterone acutely increased gonadotropin in these women. This study suggested that progesterone-related augmentation of gonadotropin release may be impaired in PCOS compared to normally cycling women, but this finding was not statistically significant.

Progesterone Actions and Resistance in Gynecological Disorders

Estrogen and progesterone and their signaling mechanisms are tightly regulated to maintain a normal menstrual cycle and to support a successful pregnancy. The imbalance of estrogen and progesterone disrupts their complex regulatory mechanisms, leading to estrogen dominance and progesterone resistance. Gynecological diseases are heavily associated with dysregulated steroid hormones and can induce chronic pelvic pain, dysmenorrhea, dyspareunia, heavy bleeding, and infertility, which substantially impact the quality of women’s lives. Because the menstrual cycle repeatably occurs during reproductive ages with dynamic changes and remodeling of reproductive-related tissues, these alterations can accumulate and induce chronic and recurrent conditions. This review focuses on faulty progesterone signaling mechanisms and cellular responses to progesterone in endometriosis, adenomyosis, leiomyoma (uterine fibroids), polycystic ovary syndrome (PCOS), and endometrial hyperplasia. We also summarize the association with gene mutations and steroid hormone regulation in disease progression as well as current hormonal therapies and the clinical consequences of progesterone resistance.

Association between the serum estrone-to-estradiol ratio and parameters related to glucose metabolism and insulin resistance in women with polycystic ovary syndrome

Objective

We aimed to evaluate associations between the ratio of serum estrone (E1) to estradiol (E2) and parameters related to serum glucose metabolism and insulin resistance in women with polycystic ovary syndrome (PCOS).

Methods

In total, 133 women between the ages of 18 and 35 diagnosed with PCOS were enrolled in this study. All participants with PCOS underwent blood tests to determine hormonal and biochemical metabolic parameters and a standard 2-hour 75-g oral glucose tolerance test. They were divided into two groups according to the serum E1-to-E2 ratio: group 1 (E1/E2 ratio <2.0) and group 2 (E1/E2 ratio ≥2.0).

Results

In the comparative analysis, the waist-to-hip ratio (WHR) was the only clinical variable that was significantly different between the two groups. Patients with a higher E1/E2 ratio showed higher fasting insulin levels, homeostasis model for insulin resistance, and postprandial glucose level at 2 hours (PPG2). In a correlation analysis, only PPG2 was significantly related to the serum E1/E2 ratio. However, after controlling for the confounding effects of body mass index (BMI) and WHR, fasting glucose was also significantly correlated with the serum E1/E2 ratio.

Conclusion

Women with PCOS with a higher serum E1/E2 ratio were found to be more likely to show higher fasting insulin and postprandial glucose levels. Significant correlations were found between the serum E1/E2 ratio and both fasting and postprandial serum glucose levels after adjusting for BMI and WHR in women with PCOS.

Cyclic Progesterone Therapy in Androgenic Polycystic Ovary Syndrome (PCOS)-A 6-Month Pilot Study of a Single Woman's Experience Changes

Background and Objectives: Women with androgenic Polycystic Ovary Syndrome (PCOS) have increased endometrial cancer risk that cyclic progesterone will prevent; it may also reverse PCOS’s neuroendocrine origins. This pilot study’s purpose was to document 6-month experience changes in a woman with PCOS taking cyclic progesterone therapy because she was intolerant of combined hormonal contraceptive therapy, the current PCOS standard of care. A 31-year-old normal-weight woman with PCOS had heavy flow, irregular cycles, and was combined hormonal contraceptives-intolerant. She was prescribed cyclic oral micronized progesterone (OMP) (300 mg/h.s. cycle days 14–27). She kept Menstrual Cycle Diary© (Diary) records, starting with the 1st treatment cycle for six cycles; she was on no other therapy. Statistical analysis a priori hypothesized progesterone decreases high estradiol (E2) experiences (flow, cervical mucus, fluid retention, front-of-the-breast tenderness and anxiety); analysis focused on these. Our objectives: (1) changes from cycles 1 to 6 in E2-related experiences; and (2) follicular phase E2-related changes from cycle 1 (no therapy) to cycles 3 and 6. Materials and Methods: Data from consecutive Diaries were entered into an SPSS database and analyzed by Wilcoxon Signed Rank Test (Objective #1) within-person whole cycle ordinal data, and (Objective #2 follicular phase) repeated measures ANOVA. Results: Cyclic OMP was associated with regular, shorter cycles (±SD) (28.2 ± 0.8 days). Comparison of cycles 1–6 showed decreased fluid retention (p = 0.001), breast tenderness (p = 0.002), and cervical mucus (p = 0.048); there were no changes in flow or anxiety. Fluid retention in the follicular phase also significantly decreased over time (F (1.2, 14.7) = 6.7, p = 0.017). Conclusions: Pilot daily Diary data suggest women with PCOS have improved everyday experiences on cyclic progesterone therapy. Larger prospective studies with more objective outcomes and randomized controlled trials of this innovative PCOS therapy are needed.

Advances in the Regulation of Mammalian Follicle-Stimulating Hormone Secretion

Simple Summary

The reproduction of mammals is regulated by the hypothalamic-pituitary-gonadal axis. Follicle stimulating hormone, as one of the gonadotropins secreted by the pituitary gland, plays an immeasurable role. This article mainly reviews the molecular basis and classical signaling pathways that regulate the synthesis and secretion of follicle stimulating hormone, and summarizes its internal molecular mechanism, which provides a certain theoretical basis for the research of mammalian reproduction regulation and the application of follicle stimulating hormone in production practice.

Abstract

Mammalian reproduction is mainly driven and regulated by the hypothalamic-pituitary-gonadal (HPG) axis. Follicle-stimulating hormone (FSH), which is synthesized and secreted by the anterior pituitary gland, is a key regulator that ultimately affects animal fertility. As a dimeric glycoprotein hormone, the biological specificity of FSH is mainly determined by the β subunit. As research techniques are being continuously innovated, studies are exploring the underlying molecular mechanism regulating the secretion of mammalian FSH. This article will review the current knowledge on the molecular mechanisms and signaling pathways systematically regulating FSH synthesis and will present the latest hypothesis about the nuclear cross-talk among the various endocrine-induced pathways for transcriptional regulation of the FSH β subunit. This article will provide novel ideas and potential targets for the improved use of FSH in livestock breeding and therapeutic development.

Androgen Suppresses In Vivo and In Vitro LH Pulse Secretion and Neural Kiss1 and Tac2 Gene Expression in Female Mice

Androgens can affect the reproductive axis of both sexes. In healthy women, as in men, elevated exogenous androgens decrease gonad function and lower gonadotropin levels; such circumstances occur with anabolic steroid abuse or in transgender men (genetic XX individuals) taking androgen supplements. The neuroendocrine mechanisms by which endogenous or exogenous androgens regulate gonadotropin release, including aspects of pulsatile luteinizing hormone (LH) secretion, remain unknown. Because animal models are valuable for interrogating neural and pituitary mechanisms, we studied effects of androgens in the normal male physiological range on in vivo LH secretion parameters in female mice and in vitro LH secretion patterns from isolated female pituitaries. We also assessed androgen effects on hypothalamic and gonadotrope gene expression in female mice, which may contribute to altered LH secretion profiles. We used a nonaromatizable androgen, dihydrotestosterone (DHT), to isolate effects occurring specifically via androgen receptor (AR) signaling. Compared with control females, DHT-treated females exhibited markedly reduced in vivo LH pulsatility, with decreases in pulse frequency, amplitude, peak, and basal LH levels. Correlating with reduced LH pulsatility, DHT-treated females also exhibited suppressed arcuate nucleus Kiss1 and Tac2 expression. Separate from these neural effects, we determined in vitro that the female pituitary is directly inhibited by AR signaling, resulting in lower basal LH levels and reduced LH secretory responses to gonadotropin-releasing hormone pulses, along with lower gonadotropin gene expression. Thus, in normal adult females, male levels of androgen acting via AR can strongly inhibit the reproductive axis at both the neural and pituitary levels.

Animal Models to Understand the Etiology and Pathophysiology of Polycystic Ovary Syndrome

More than 1 out of 10 women worldwide are diagnosed with polycystic ovary syndrome (PCOS), the leading cause of female reproductive and metabolic dysfunction. Despite its high prevalence, PCOS and its accompanying morbidities are likely underdiagnosed, averaging > 2 years and 3 physicians before women are diagnosed. Although it has been intensively researched, the underlying cause(s) of PCOS have yet to be defined. In order to understand PCOS pathophysiology, its developmental origins, and how to predict and prevent PCOS onset, there is an urgent need for safe and effective markers and treatments. In this review, we detail which animal models are more suitable for contributing to our understanding of the etiology and pathophysiology of PCOS. We summarize and highlight advantages and limitations of hormonal or genetic manipulation of animal models, as well as of naturally occurring PCOS-like females.

Accelerated Episodic Luteinizing Hormone Release Accompanies Blunted Progesterone Regulation in PCOS-like Female Rhesus Monkeys (Macaca Mulatta) Exposed to Testosterone during Early-to-Mid Gestation

BACKGROUND/AIMS

Ovarian theca cell hyperandrogenism in women with polycystic ovary syndrome (PCOS) is compounded by androgen receptor-mediated impairment of estradiol and progesterone negative feedback regulation of episodic luteinizing hormone (LH) release. The resultant LH hypersecretion, likely the product of accelerated episodic release of gonadotropin-releasing hormone (GnRH) from the median eminence of the hypothalamus, hyperstimulates ovarian theca cell steroidogenesis, enabling testosterone (T) and androstenedione excess. Prenatally androgenized (PA) female monkeys exposed to fetal male levels of T during early-to-mid gestation, when adult, demonstrate PCOS-like traits, including high T and LH levels. This study tests the hypothesis that progesterone resistance-associated acceleration in episodic LH release contributes to PA monkey LH excess.

METHODS

A total of 4 PA and 3 regularly cycling, healthy control adult female rhesus monkeys of comparable age and body mass index underwent (1) a 10 h, frequent intravenous sampling assessment for LH episodic release, immediately followed by (2) IV infusion of exogenous GnRH to quantify continuing pituitary LH responsiveness, and subsequently (3) an SC injection of a progesterone receptor antagonist, mifepristone, to examine LH responses to blockade of progesterone-mediated action.

RESULTS

Compared to controls, the relatively hyperandrogenic PA females exhibited ~100% increase (p = 0.037) in LH pulse frequency, positive correlation of LH pulse amplitude (p = 0.017) with androstenedione, ~100% greater increase (p = 0.034) in acute (0-10 min) LH responses to exogenous GnRH, and an absence (p = 0.008) of modest LH elevation following acute progesterone receptor blockade suggestive of diminished progesterone negative feedback.

CONCLUSION

Such dysregulation of LH release in PCOS-like monkeys implicates impaired feedback control of episodic release of hypothalamic GnRH reminiscent of PCOS neuroendocrinopathy.

Exaggerated glucagon responses to hypoglycemia in women with polycystic ovary syndrome

CONTEXT

Premenopausal women have blunted counter-regulatory hormone responses (CRR) to hypoglycemia compared to men. Postmenopausal women have CRR similar to men; the premenopausal pattern can be restored by estrogen. However, glucagon and pancreatic polypeptide (PP) responses remain lower in postmenopausal women than in men. Since hyperandrogenemia contributes to the metabolic phenotype of polycystic ovary syndrome (PCOS), we hypothesize that CRR to hypoglycemia especially of glucagon and PP is exaggerated in premenopausal women with PCOS compared to premenopausal control women.

STUDY SUBJECTS AND METHODS

Ten obese women with PCOS and 9 control women of similar ethnicity, age and BMI underwent determination of CRR in response to hypoglycemia during 180-min 60mU/m²/min insulin dose hypoglycemic clamp with isotopic assessment of endogenous glucose production (EGP). To assess CRR to hypoglycemia, glucagon, cortisol, growth hormone (GH), epinephrine, norepinephrine, PP, lactate, free fatty acid (FFA), β-hydroxybutyrate, and glycerol levels were sampled at 15-min intervals throughout the clamp.

MAIN FINDINGS

Incremental glucagon levels were ~3-fold higher during hypoglycemia (P=0.03) in PCOS. Postabsorptive, steady-state and incremental GH, cortisol, epinephrine, norepinephrine, PP, FFA, glycerol and β-hydroxybutyrate did not differ. At target glucose levels of ~52mg/dL, insulin mediated glucose disposal (IMGD) was decreased by ~40% (P=0.02) in PCOS, compared to control women, despite ~20% higher steady-state insulin levels (P=0.03). Neither postabsorptive nor steady-state EGP differed. However, postabsorptive lactate levels were ~50% higher (P=0.02). PCOS status (P=0.04) and IMGD (P=0.02) predicted the differential glucagon response to hypoglycemia in separate regression models, however, neither parameter remained an independent predictor in a combined model.

PRINCIPAL CONCLUSIONS

Glucagon responses were increased in PCOS, whereas other CRR did not differ. Women with PCOS were insulin resistant under hypoglycemic conditions and higher postabsorptive lactate levels in PCOS were consistent with this finding. Insulin resistance may have contributed to exaggerated glucagon response to hypoglycemia in PCOS.

Effect of maternal PCOS and PCOS-like phenotype on the offspring's health

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder with both reproductive and metabolic abnormalities affecting women of reproductive age. While the exact origin of PCOS is unknown, observations from clinical and animal studies suggest that maternal hyperandrogenism may be a contributing factor. Because women with PCOS manifest hyperandrogenism during pregnancy, changes in the gestational endocrine milieu may play a role in the vertical transmission of this syndrome. This review discusses the potential developmental origins of PCOS, the impact of maternal PCOS on the offspring's health and contributions of the postnatal environment, capitalizing on findings from animal models that exhibit a PCOS-like phenotype. In addition, this review highlights the scarcity of data at early gestational stages in humans and the importance of animal experimentation to better understand the cellular and molecular mechanisms involved in the programming of adult diseases, therefore, helping identify therapeutic targets for preventive and treatment strategies.

Effects of BMAL1-SIRT1-positive cycle on estrogen synthesis in human ovarian granulosa cells: an implicative role of BMAL1 in PCOS

Brain and muscle ARNT-like protein 1 (BMAL1) is necessary for fertility and has been found to be essential to follicle growth and steroidogenesis. Sirtuin1 (SIRT1) has been reported to interact with BMAL1 and function in a circadian manner. Evidence has shown that SIRT1 regulates aromatase expression in estrogen-producing cells. We aimed to ascertain if there is a relationship between polycystic ovary syndrome (PCOS) and BMAL1, and whether and how BMAL1 takes part in estrogen synthesis in human granulosa cells (hGCs). Twenty-four women diagnosed with PCOS and 24 healthy individuals undergoing assisted reproduction were studied. BMAL1 expression in their granulosa cells (GCs) was observed by quantitative real-time polymerase chain reaction (qRT-PCR). The level of expression in the PCOS group was lower than that of the group without PCOS (p < 0.05). We also analyzed estrogen synthesis and aromatase expression in KGN cell lines. Both were downregulated after BMAL1 and SIRT1 knock-down and, conversely, upregulated after overexpression treatments of these two genes in KGN cells. Both BMAL1 and SIRT1 had a mutually positive regulation, as did the phosphorylation of JNK. Furthermore, JNK overexpression increased estrogen synthesis activity and the expression levels of aromatase, BMAL1, and SIRT1. In KGN and hGCs, estrogen synthesis and aromatase expression were downregulated after treatment with JNK and SIRT1 inhibitors. In addition, BMAL1, SIRT1, and JNK expression levels were all downregulated. Our results demonstrate the effects of BMAL1 on estrogen synthesis in hGCs and suggest a BMAL1-SIRT1-JNK positive feedback cycle in this process, which points out an important role of BMAL1 in the development of PCOS.

Role of Prolactin in the Polycystic Ovary Syndrome

Studies with a dopamine agonist (Bromocriptine) and an antagonist (Haloperidol) suggest that elevated sex steroid synthesis such as may be found in the polycystic ovary syndrome (PCO) influence the pituitary lactotrope response to endogenous control mechanisms. A distinction between PCO with occasional elevation of plasma prolactin (PRL) and the galactorrhoea-amenorrhoea syndrome (GA) associated with hyperprolactinaemia can be established on the basis of differences in circulating levels of sex steroids and in the pattern of response to lactotrope cell stimulation. Thus, adrenal androgen synthesis can be strengthened in GA whereas in PCO both pathways, adrenal and ovarian, may be overstimulated. Also blunted PRL response to TRH or dopaminergic blockade is often seen in GA. The use of bromocriptine in patients with PCO and elevated PRL plasma levels has been shown to restore ovulation. The possible implications of dopaminergic mechanisms in the control of LH secretion independent of PRL release are discussed.

A Novel Letrozole Model Recapitulates Both the Reproductive and Metabolic Phenotypes of Polycystic Ovary Syndrome in Female Mice

Polycystic ovary syndrome (PCOS) pathophysiology is poorly understood, due partly to lack of PCOS animal models fully recapitulating this complex disorder. Recently, a PCOS rat model using letrozole (LET), a nonsteroidal aromatase inhibitor, mimicked multiple PCOS phenotypes, including metabolic features absent in other models. Given the advantages of using genetic and transgenic mouse models, we investigated whether LET produces a similar PCOS phenotype in mice. Pubertal female C57BL/6N mice were treated for 5 wk with LET, which resulted in increased serum testosterone and normal diestrus levels of estradiol, similar to the hyperandrogenemia and follicular phase estrogen levels of PCOS women. As in PCOS, ovaries from LET mice were larger, polycystic, and lacked corpora lutea versus controls. Most LET females were acyclic, and all were infertile. LET females displayed elevated serum LH levels and higher Lhb mRNA in the pituitary. In contrast, serum FSH and Fshb were significantly reduced in LET females, demonstrating differential effects on gonadotropins, as in PCOS. Within the ovary, LET females had higher Cyp17, Cyp19, and Fsh receptor mRNA expression. In the hypothalamus, LET females had higher kisspeptin receptor mRNA expression but lower progesterone receptor mRNA levels. LET females also gained more weight than controls, had increased abdominal adiposity and adipocyte size, elevated adipose inflammatory mRNA levels, and impaired glucose tolerance, mirroring the metabolic phenotype in PCOS women. This is the first report of a LET paradigm in mice that recapitulates both reproductive and metabolic PCOS phenotypes and will be useful to genetically probe the PCOS condition.

The management of patients with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women. The syndrome is typified by its heterogeneous presentation, which includes hirsutism (a function of hypersecretion of ovarian androgens), menstrual irregularity and infertility (that is due to infrequent or absent ovulation). Furthermore, PCOS predisposes patients to metabolic dysfunction and an increased risk of type 2 diabetes mellitus (T2DM). The aetiology of the syndrome has a major genetic component. Obesity exacerbates the insulin resistance that is a feature of PCOS in many women and amplifies the clinical and biochemical abnormalities. In clinical practice, the choice of investigations to be done depends mainly on the presenting symptoms. The approach to management is likewise dependent on the presenting complaint. Symptoms of androgen excess (hirsutism, acne and alopecia) require cosmetic measures, suppression of ovarian androgen function and anti-androgen therapy, alone or in combination. Ovulation rate is improved by diet and lifestyle intervention in overweight individuals but induction of ovulation by, in the first instance, anti-estrogens is usually required. Monitoring of glucose is important in overweight women and/or those with a family history of T2DM. Metformin is indicated for women with impaired glucose tolerance but whether this drug is otherwise useful in women with PCOS remains debatable.

Ovarian epithelial tumors and reproductive factors: a systematic review

PURPOSE

The aim of this systematic review is to summarize the current knowledge about the etiology and pathogenesis of borderline tumors ovarian cancer with special emphasis on the role of endocrine treatments and reproductive factors to establish a foundation for future studies.

METHODS

We performed a systematic review on the relation between ovarian epithelial tumors (OET) and reproductive factors using the keywords: ovarian cancer, ovarian tumor, ovarian borderline tumor, age at menarche, age at menopause, parity, infertility, PCO syndrome, oral contraception, menopausal hormone therapy, fertility treatment. Totally, 3,290 abstracts were scanned for their relevance in this publication and 127 were finally included.

RESULTS

The incidence of ovarian epithelial cancer and ovarian borderline tumors is influenced by certain reproductive factors. The strongest protective effects are conferred by parity and use of oral contraceptive pills. Recent molecular biologic and histopathologic studies prove that OET represent a diverse group of tumors, each histologic type with a different genetic background. This is at least partly reflected in epidemiologic and clinical studies showing different risk modulating effects of reproductive factors and endocrine therapies on OET.

CONCLUSIONS

The etiology and pathogenesis of ovarian cancer are still not fully understood. None of the so far proposed hypothesis on the development of OET can fully account for the epidemiologic and clinical findings in the context of reproductive factors and OET development. Further research approaches are warranted and need to put more weight on the clinical and genetical diversity of OET to yield a more detailed insight into their pathogenesis.

Insulin resistance and the polycystic ovary syndrome revisited: an update on mechanisms and implications

Polycystic ovary syndrome (PCOS) is now recognized as an important metabolic as well as reproductive disorder conferring substantially increased risk for type 2 diabetes. Affected women have marked insulin resistance, independent of obesity. This article summarizes the state of the science since we last reviewed the field in the Endocrine Reviews in 1997. There is general agreement that obese women with PCOS are insulin resistant, but some groups of lean affected women may have normal insulin sensitivity. There is a post-binding defect in receptor signaling likely due to increased receptor and insulin receptor substrate-1 serine phosphorylation that selectively affects metabolic but not mitogenic pathways in classic insulin target tissues and in the ovary. Constitutive activation of serine kinases in the MAPK-ERK pathway may contribute to resistance to insulin's metabolic actions in skeletal muscle. Insulin functions as a co-gonadotropin through its cognate receptor to modulate ovarian steroidogenesis. Genetic disruption of insulin signaling in the brain has indicated that this pathway is important for ovulation and body weight regulation. These insights have been directly translated into a novel therapy for PCOS with insulin-sensitizing drugs. Furthermore, androgens contribute to insulin resistance in PCOS. PCOS may also have developmental origins due to androgen exposure at critical periods or to intrauterine growth restriction. PCOS is a complex genetic disease, and first-degree relatives have reproductive and metabolic phenotypes. Several PCOS genetic susceptibility loci have been mapped and replicated. Some of the same susceptibility genes contribute to disease risk in Chinese and European PCOS populations, suggesting that PCOS is an ancient trait.

Endocrine antecedents of polycystic ovary syndrome in fetal and infant prenatally androgenized female rhesus monkeys

Experimentally induced fetal androgen excess induces polycystic ovary syndrome-like traits in adult female rhesus monkeys (Macaca mulatta). Developmental changes leading to this endocrinopathy are not known. We therefore studied 15 time-mated, gravid female rhesus monkeys with known female fetuses. Nine dams received daily s.c. injections of 15 mg of testosterone propionate (TP), and six received injections of oil vehicle (control) from 40 through 80 days of gestation (term, 165 days; range, +/-10 days). All fetuses were delivered by cesarean section using established methods at term. Ultrasound-guided fetal blood sample collection and peripheral venous sample collection of dams and subsequent infants enabled determination of circulating levels of steroid hormones, LH and FSH. The TP injections elevated serum testosterone and androstenedione levels in the dams and prenatally androgenized (PA) fetuses. After cessation of TP injections, testosterone levels returned to values within the reference range for animals in these age groups, whereas serum androstenedione levels in PA infants were elevated. The TP injections did not increase estrogen levels in the dams or the PA fetuses or infants, yet conjugated estrogen levels were elevated in the TP-injected dams. Serum levels of LH and FSH were elevated in late-gestation PA fetuses, and LH levels were elevated in PA infants. These studies suggest that experimentally induced fetal androgen excess increases gonadotropin secretion in PA female fetuses and infants and elevates endogenous androgen levels in PA infants. Thus, in this nonhuman primate model, differential programming of the fetal hypothalamo-pituitary unit with concomitant hyperandrogenism provides evidence to suggest developmental origins of LH and androgen excess in adulthood.

Polycystic ovary syndrome: clinical and imaging features

Polycystic ovary syndrome is the most common endocrine disorder occurring in reproductive-age women. The syndrome is complex, multifactorial, and not always easily defined. Diagnosis is based upon a combination of clinical and biochemical criteria and ovarian morphology. The following review describes the clinical features, pathophysiology, diagnosis, and the role of imaging. Diagnostic imaging techniques are discussed, with emphasis on ultrasound as the main modality used worldwide. Contributions of 3-dimensional and Doppler ultrasound are addressed in addition to potential indications for magnetic resonance imaging in the evaluation of patients with suspected polycystic ovary syndrome.

Androgen excess fetal programming of female reproduction: a developmental aetiology for polycystic ovary syndrome?

The aetiology of polycystic ovary syndrome (PCOS) remains unknown. This familial syndrome is prevalent among reproductive-aged women and its inheritance indicates a dominant regulatory gene with incomplete penetrance. However, promising candidate genes have proven unreliable as markers for the PCOS phenotype. This lack of genetic linkage may represent both extreme heterogeneity of PCOS and difficulty in establishing a universally accepted PCOS diagnosis. Nevertheless, hyperandrogenism is one of the most consistently expressed PCOS traits. Animal models that mimic fetal androgen excess may thus provide unique insight into the origins of the PCOS syndrome. Many female mammals exposed to androgen excess in utero or during early post-natal life typically show masculinized and defeminized behaviour, ovulatory dysfunction and virilized genitalia, although behavioural and ovulatory dysfunction can coexist without virilized genitalia based upon the timing of androgen excess. One animal model shows particular relevance to PCOS: the prenatally androgenized female rhesus monkey. Females exposed to androgen excess early in gestation exhibit hyperandrogenism, oligomenorrhoea and enlarged, polyfollicular ovaries, in addition to LH hypersecretion, impaired embryo development, insulin resistance accompanying abdominal obesity, impaired insulin response to glucose and hyperlipidaemia. Female monkeys exposed to androgen excess late in gestation mimic these programmed changes, except for LH and insulin secretion defects. In utero androgen excess may thus variably perturb multiple organ system programming and thereby provide a single, fetal origin for a heterogeneous adult syndrome.

PCOS: an ovarian disorder that leads to dysregulation in the hypothalamic–pituitary–adrenal axis?

This review focuses on the role of the ovaries in the pathogenesis of the polycystic ovarian syndrome. In particular, the failure of follicular development, hypothalamo-pituitary dysregulation, alterations in adrenal steroid output and derangement of intermediary metabolism are discussed in the context of the ovaries. It is concluded that the central and adrenal alterations associated with PCOS are unlikely to be primary but rather are secondary to the events within the ovary.

The pathophysiology of polycystic ovary syndrome: trying to understand PCOS and its endocrinology

The pathophysiology of the polycystic ovary syndrome (PCOS) encompasses inherent ovarian dysfunction that is strongly influenced by external factors, such as disturbances of the hypothalamic-pituitary-ovarian axis and hyperinsulinaemia. Exaggerated gonadotrophin releasing hormone (GnRH) pulsatility results in hypersecretion of luteinising hormone (LH), which has effects both on ovarian androgen production and oocyte development. Disturbed ovarian-pituitary and hypothalamic feedback accentuates the 0gonadotrophin abnormalities. Hyperinsulinaemia is secondary both to insulin resistance at the periphery and to abnormal pancreatic beta cell function. PCOS runs in families and a number of genetic abnormalities appear to result in features of the syndrome and account for the heterogeneity of the symptoms. Environmental influences, such as nutrition and lifestyle, further influence expression of the syndrome.

Relationship of GnRH-stimulated LH release to episodic LH secretion and baseline endocrine-metabolic measures in women with polycystic ovary syndrome

BACKGROUND AND OBJECTIVE

In polycystic ovary syndrome (PCOS) inappropriate gonadotrophin secretion is characterized by increased pulse frequency and amplitude, elevated 24-h mean serum concentrations, and greater responses to GnRH. While the mechanism(s) responsible for this increased release of LH are not well understood, enhanced LH secretion has been attributed to increased pituitary sensitivity to GnRH and feedback influences from circulating steroid hormones. To address these considerations, we conducted a study to examine the relationships between GnRH-stimulated LH responses, episodic gonadotrophin secretion, and baseline measurements of endocrine-metabolic function in PCOS.

PATIENTS

Serum LH responses to sequential multidose GnRH administration and pulsatile gonadotrophin secretion were examined in 13 PCOS and 13 normal women.

MEASUREMENTS

Serum LH, steroid hormone, insulin and glucose levels were determined in blood samples obtained during assessment of episodic gonadotrophin secretion and LH responses to GnRH stimulation.

DESIGN

Each subject was studied on two consecutive days. On study day 1 each subject underwent frequent blood sampling every 10 min for 12 h. On study day 2 each received sequential doses of GnRH, 2 microg, 10 microg and 20 microg, administered intravenously at 4-h intervals over a continuous 12-h period.

RESULTS

Serum LH responses following GnRH were markedly greater in PCOS compared to normal women, as expected. In individual PCOS, peak LH responses to GnRH were significantly correlated with corresponding basal LH and LH pulse amplitude, but not LH pulse frequency. In the PCOS group, LH responses were positively correlated with serum oestradiol (E2) and inversely related to body mass index (BMI). Between-group differences in LH responsiveness disappeared when controlling for serum testosterone (T) levels.

CONCLUSIONS

These results indicate that the absolute LH increment following GnRH is largely dependent on baseline LH levels and may account for the well-documented difference in LH responsiveness between PCOS and normal women. That neither LH responses to GnRH nor LH pulse amplitude were correlated to LH pulse frequency suggests involvement of other factors along with GnRH to account for increased LH secretion in PCOS. In addition to E2 and BMI, serum testosterone appears to be, at least in part, responsible for differences in LH secretion and release between PCOS and normal women.

The effect of herbal medicine on nerve growth factor in estradiol valerate-induced polycystic ovaries in rats

A type of polycystic ovary resembling some aspects of human polycystic ovarian syndrome (PCOS) can be induced in the rat with a single injection of long-acting estradiol valerate. Among several theories behind the development of polycystic ovaries (PCO), the involvement of the sympathetic nervous system draws much attention, and herbal medicine is known to relieve the abnormal symptoms of PCO. Two herbal formulas, Changbudodam-Tang (cang fu dao tan tang) and Yongdamsagan-Tang (long dan xie gan tang), were used in the present study. The administration of herbal medicine was done every other day for 60 days. The morphological changes of ovaries from herbal medicine treatment were compared to those from an oil-treated control group and an estradiol valerate-injected group. This study also examined the possible hypothesis of neurogenic participation in terms of nerve growth factor (NGF) in the pathology of ovarian dysfunction. The nerve growth factor was analyzed in the central nervous system and ovaries by immunohistochemistry. The main findings of the present study were: (1) PCO were fully developed in rats with a single intramuscular injection of estradiol valerate, (2) PCO resulted in the expression of NGF in the ovaries and the brain tissues, and (3) herbal medicine administration significantly decreased the elevated NGF staining in the ovaries without affecting the brain tissues significantly.

Insulin sensitivity and fertility

This review sets in context significant recent advances in the understanding of the pathophysiology of polycystic ovary syndrome (PCOS). The occurrence of variable insulin sensitivity in individuals is discussed. Information is presented to demonstrate that prolonged anovulation decreases insulin sensitivity and, conversely, that improvement in insulin sensitivity normalizes ovarian function in PCOS. In addition, a meta-analysis of studies on metformin and troglitazone treatment in PCOS is presented.

Barbiturates inhibit progesterone synthesis in cultured Leydig tumor cells and human granulosa cells

Screening drugs used in obstetrical practice for effects on steroid hormone synthesis revealed that phenobarbital inhibited progesterone synthesis in MA-10 Leydig tumor cells. The inhibition was apparently a drug class effect since it could be reproduced by other barbiturates. Barbiturate blockade was reversible and could be bypassed in the MA-10 cells by using 22-hydroxycholesterol. Human granulosa cell progesterone synthesis was also inhibited in a dose dependent fashion by phenobarbital, secobarbital and barbituric acid. Significant inhibition occurred in dose ranges that would be therapeutic for treating epilepsy. From these data we conclude that barbiturates block steroidogenesis by inhibiting cholesterol transport to the cholesterol side chain cleavage enzyme.

Adipocyte insulin action following ovulation in polycystic ovarian syndrome

The role of anovulation and insulin resistance in the pathogenesis of polycystic ovarian syndrome (PCOS) remains to be determined. The aim of this study was to investigate whether the metabolic abnormality of insulin resistance in PCOS reflects, rather than causes, the ovarian dysfunction. Eight subjects with classical PCOS were studied on two occasions. Adipocyte insulin sensitivity together with hormonal and metabolic changes were investigated in patients with PCOS following prolonged amenorrhoea and then again in the early follicular phase after ovulation. Insulin receptor binding in amenorrhoeic subjects with PCOS was low at 0.78 +/- 0.08% and this increased to 1.18 +/- 0.19% after an ovulatory cycle (P < 0.05). Maximal insulin stimulated 3-O-methylglucose uptake was 0.70 +/- 0. 14 during amenorrhoea and increased to 1.08 +/- 0.25 pmol/10 cm(2) cell membrane (P < 0.05). Plasma testosterone fell (4.0 +/- 0.4 to 2. 3 +/- 0.2 nmol/l; P < 0.001), luteinizing hormone fell (17.6 +/- 2.3 to 6.7 +/- 0.8 IU/l; P < 0.001) but plasma insulin concentrations remained unchanged following ovulation (14.6 +/- 1.9 and 15.7 +/- 3. 8 pmol/l during amenorrhoea and after ovulation respectively). The results of this study suggest that chronic anovulation per se appears to modify the factors contributing to cellular insulin resistance seen in PCOS.

Polycystic ovary syndrome

Polycystic ovary syndrome is a syndrome and not a disease. It reflects multiple potential etiologies and variable clinical presentations that are reviewed in this article. In addition to menstrual dysfunction and hyperandrogenism, women with polycystic ovary syndrome also may have hypothalamic-pituitary abnormalities, polycystic ovaries on pelvic ultrasonography, infertility, obesity, and insulin resistance. A familial pattern occurs in some cases, suggesting a genetic component to the disorder. The three major pathophysiologic hypotheses that have been proposed to explain the clinical findings of the disorder as well as treatment options are reviewed in this article.

Inhibin A and inhibin B in women with polycystic ovarian syndrome during treatment with FSH to induce mono-ovulation

OBJECTIVE

Polycystic ovary syndrome (PCOS) is characterized by the presence of numerous small antral follicles arrested at a diameter of less than 10 mm. As development of large antral follicle(s) can be stimulated by the administration of FSH, it has been suggested that the arrest of follicle development is due to a relative lack of or resistance to FSH. We have measured the concentration of FSH and LH and the ovarian hormones oestradiol, inhibin A and B, in relation to the dynamics of follicular development in women with PCOS under basal conditions and during treatment with FSH.

DESIGN

The concentrations of FSH, LH, oestradiol, inhibin A and B were measured in women with PCOS who were untreated (n = 9) or following progesterone-induced menses (10 cycles in six women) and control women on day 3 of a normal cycle (n = 10). Serial measurements of the same hormones were made during induction of ovulation with low dose of exogenous FSH in the women with PCOS who had been treated with progesterone. The dynamics of follicle development were measured by serial pelvic ultrasound examinations during treatment with FSH in PCOS and in the follicular phase of control cycles.

PATIENTS

Nine anovulatory untreated women with PCOS were compared with 10 normal women and six women with PCOS undergoing FSH treatment.

RESULTS

The concentrations of inhibin B and LH were higher in both groups of women with PCOS than in normal control women on day 3. In untreated women with PCOS the concentration of inhibin A was also significantly elevated compared to control women (P < 0.01) but not in women pretreated with progesterone. Basal concentrations of oestradiol were also significantly higher in women with PCOS than in the early follicular phase of the normal cycle. There were no significant differences in the concentration of FSH between the groups. Treatment of women with PCOS with low doses of FSH stimulated the development of a single dominant follicle which had an identical rate of growth and secretion of oestradiol and inhibin A to that observed in spontaneous cycles in normal women. In contrast to normal women, the concentration of inhibin B rose 7-fold following FSH treatment and remained elevated until the luteal phase.

CONCLUSIONS

The raised concentrations of inhibin A and B in women with PCOS probably reflects the increased number of small antral follicles characteristically present in that condition. The striking similarity in the dynamics of growth of the dominant follicle and the pattern in concentration of oestradiol and inhibin A in normal women and in women with PCOS treated with modest amounts of FSH, suggests that the arrest of follicle development in PCOS may be due to a relative deficiency of FSH which may in turn be secondary to increased secretion of either or both inhibin forms.

Determinants of abnormal gonadotropin secretion in clinically defined women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder of reproductive age women characterized in its broadest definition by the presence of oligoamenorrhea and hyperandrogenism and the absence of other disorders. Defects of gonadotropin secretion, including an elevated LH level, elevated LH to FSH ratio, and an increased frequency and amplitude of LH pulsations have been described, but the prevalence of these defects in a large, unbiased population of PCOS patients has not been determined. Sixty-one women with PCOS defined by oligomenorrhea and hyperandrogenism and 24 normal women in the early follicular phase had LH samples obtained every 10 min for 8-12 h. Pool LH levels from the frequent sampling studies were within the normal range in the 9 PCOS patients (14.8%) who were studied within 21 days after a documented spontaneous ovulation. Excluding these post-ovulatory patients, 75.0% of the PCOS patients had an elevated pool LH level (above the 95th percentile of the normal controls), and 94% had an elevated LH to FSH ratio. In the anovulatory PCOS patients, pool LH correlated positively with 17-OH progesterone (R = 0.30, P = 0.03), but not with estradiol, estrone, testosterone, androstenedione, or DHEA-S. Pool LH and LH to FSH ratio correlated positively with LH pulse frequency (R = 0.40, P = 0.004 for pool LH, and R = 0.39; P = 0.005 for LH/FSH). There was also a strong negative correlation between pool LH and body mass index (BMI) (R = -0.59, P < 10(-5)). The relationship between BMI and LH secretion in the PCOS patients appeared to be strongest with body fatness, as pool LH was correlated inversely with percent body fat, whether measured by skinfolds (R = -0.61, P < 10(-5)), bioimpedance (R = -0.55, P < 10(-4)), or dual energy x-ray absorptiometry (DEXA) (R = -0.70, P = 0.001; n = 18 for DEXA only). By DEXA, the only body region that was highly correlated with pool LH was the trunk (R = -0.71, P = 0.001). The relationship between body fatness and LH secretion occurred via a decrease in LH pulse amplitude (R = -0.63, P < 10(-5) for BMI; R = -0.58, P < 10(-4) for bioimpedance; and R = -0.64, P = 0.004 for whole body DEXA), with no significant change in pulse frequency with increasing obesity (R = -0.17, P = 0.23 for BMI).

IN CONCLUSION

1) the prevalence of gonadotropin abnormalities is very high in women with PCOS selected on purely clinical grounds, but is modified by recent spontaneous ovulation; 2) the positive relationship between LH pulse frequency and both pool LH and LH to FSH ratio supports the hypothesis that a rapid frequency of GnRH secretion may play a key etiologic role in the gonadotropin defect in PCOS patients; 3) pool LH and LH pulse amplitude are inversely related to body mass index and percent body fat in a continuous fashion; and 4) the occurrence of a continuous spectrum of gonadotropin abnormalities varying with body fat suggests that nonobese and obese patients with PCOS do not represent distinct pathophysiologic subsets of this disorder.

Linkage and association of insulin gene VNTR regulatory polymorphism with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting up to 10% of women of reproductive age. Women with anovulatory PCOS have hyperinsulinaemia, insulin resistance, and dyslipidaemia, and the syndrome is associated with greatly increased risks of non-insulin-dependent diabetes mellitus and cardiovascular disease and it often clusters in families. The VNTR (variable number of tandem repeats) locus upstream of the insulin gene (INS) regulates insulin expression. We have studied INS VNTR as a candidate genetic locus for susceptibility to PCOS.

METHODS

We evaluated linkage of PCOS to the INS VNTR locus on chromosome 11p15.5 in 17 families with several cases, and looked for an association between VNTR and PCOS in two additional clinic populations. VNTR genotypes were designated I/I, I/III, and III/III and linkage disequilibrium mapping was used to test the primary role of the VNTR.

FINDINGS

In a group of PCOS/male pattern baldness families, we obtained positive evidence for linkage to 11p15.5 (p = 0.002). The INS VNTR III/III genotype was associated with an increased risk of PCOS in two independent case-control studies (odds ratios 8.20 [p = 0.005] and 5.70 [p = 0.043]). Multilocus linkage disequilibrium mapping suggests that VNTR itself is the predisposing locus.

INTERPRETATION

Mapping of susceptibility to PCOS to the INS VNTR implies that PCOS is due, in part, to an inherited alteration in insulin production. The data suggest a mechanistic link between type 2 diabetes and PCOS, which is a risk factor for diabetes later in life.

Spontaneous follicular and luteal function in infertile women with oligomenorrhoea: role of luteinizing hormone

OBJECTIVE

There is a paucity of longitudinal endocrine studies of infertile patients with oligomenorrhoea. We have assessed the frequency and quality of spontaneous follicular development and luteal function in patients with oligomenorrhoea and infertility (PCOS), and have related the observed criteria to circulating LH activity.

DESIGN

Prospective detailed investigations in a cohort of unselected patients.

PATIENTS

Infertile women with oligomenorrhoea (PCOS, n = 131) presenting to the infertility clinic at the Royal Infirmary, Glasgow.

MEASUREMENTS

Patients were monitored with frequent plasma oestradiol (E2) concentration assessments over a minimum period of 3 weeks, starting more than 2 weeks after a menstrual bleed. When follicular maturation was identified the patient provided daily blood samples through to her ensuing menstrual bleed, and E2, progesterone, total testosterone, FSH and LH were assessed in these samples. Luteal phase progesterone profiles were assessed between the days LH surge +2 and LH surge +6 by means of a progesterone index.

RESULTS

Forty-eight per cent of the patients showed evidence of follicular development. The oestradiol profiles in the patients showing follicular growth were normal, but the progesterone curve was sub-normal in the early luteal phase, due to a high proportion of deficient luteal phases. The mean LH concentrations were elevated in the whole group, but no difference was observed between the mean LH values for those patients showing spontaneous follicular development and those who did not, and the incidence of ovulation was similar in the normal LH and elevated LH groups. Similarly, no relation was established between LH and the quantitative assessment of luteal phase progesterone profiles (progesterone index), and the distribution of progesterone indices was similar in the normal LH and elevated LH groups. Testosterone concentrations were positively correlated with LH (p = 0.008) but not with the incidence of spontaneous follicular growth. There was no significant difference in the incidence of spontaneous ovulation between the patients with elevated or normal mean follicular phase testosterone concentrations.

CONCLUSION

The data indicate that both LH and testosterone secretion in PCOS were closely linked, but that neither was directly linked to the incidence or inhibition of spontaneous follicular development in PCOS, or to the disturbance in luteal phase progesterone profiles.

Severe impairment of insulin action in adipocytes from amenorrheic subjects with polycystic ovary syndrome

Adipose tissue was used to characterize the metabolic abnormality of insulin resistance in polycystic ovary syndrome (PCOS). Nine patients with PCOS were studied during a period of amenorrhea and confirmed to be chronically anovulatory by vaginal ultrasound and plasma progesterone measurements. These were compared with six age- and body mass index (BMI)-matched controls (BMI, 27.2 +/- 2.2 in PCOS and 24.7 +/- 2.3 in control subjects). Insulin receptor binding was measured and insulin action was assessed by measuring initial rates of 3-O-methylglucose uptake and by inhibition of lipolysis. The maximum specific insulin receptor binding was 0.62% +/- 0.12% and 1.78% +/- 0.18% per 10-cm2 cell surface (mean +/- SEM) in PCOS and control subjects, respectively (P < .001). Maximum rates of glucose transport were also impaired as compared with controls, with 3-O-methylglucose transport being 0.90 +/- 0.15 versus 1.57 +/- 0.28 pmol/10 cm2/5 s, respectively (P < .05). The concentration of insulin required for half-maximal stimulation of glucose uptake was 165 +/- 36 versus 32 +/- 10 pmol in PCOS and control subjects, respectively (P < .05). The maximum percentage lipolysis inhibition (mean +/- SEM) was 9.5% +/- 1.6% in PCOS and 28.3% +/- 7.2% in control patients, respectively (P < .01). These data demonstrate that there are both insulin binding and postreceptor defects in adipocytes from amenorrheic PCOS subjects. The degree of defect in adipocyte insulin action is greater than would have been anticipated from in vivo data.

The independent effects of polycystic ovary syndrome and obesity on serum concentrations of gonadotrophins and sex steroids in premenopausal women

OBJECTIVE

To investigate the basal levels of gonadotrophins and sex steroids, with special reference to the effects of obesity and body fat distribution, in premenopausal women, both those with polycystic ovary syndrome (PCOS) and those with normal ovaries and regular menstrual cycles.

DESIGN

Cross-sectional study. The separate effects of obesity (and body fat distribution and fasting insulin levels) and PCOS on endocrine variables were evaluated by means of analysis of covariance.

PATIENTS

Sixty-seven women with anovulatory menstrual cycles and polycystic ovaries according to ultrasonography and 59 women with normal ovaries and regular cycles, both groups covering a wide range of body mass index (BMI, PCOS, 17.6-37.4, mean 25.7 kg/m2; controls, 18.8-40.9, mean 25.1 kg/m2).

MEASUREMENTS

Serum levels of gonadotrophins, sex steroid hormones, prolactin and GH obtained in the early follicular phase in the controls, fasting insulin levels, anthropometric measures (BMI, skinfolds, waist hip ratio).

RESULTS

Mean serum concentrations of LH, androstenedione, testosterone, the free androgen index (FAI; all P < 0.0001) and DHEAS (P < 0.01) were higher, and serum FSH (P < 0.01) and serum SHBG levels lower (P < 0.0001), in the PCOS group than in the controls. Women with PCOS had a more pronounced upper body fat distribution and higher fasting insulin levels than the controls. Independent of PCOS, BMI was positively associated with serum levels of FSH (P < 0.001) and negatively with levels of LH (P < 0.05), LH/FSH ratio (P < 0.0001), SHBG (P < 0.0001) and androstenedione (P < 0.01), whereas for levels of testosterone, FAI and DHEAS the impact of obesity differed significantly between the groups. Thus, in the PCOS group, testosterone levels (P < 0.05) and the FAI (P < 0.001) were positively associated with BMI, whereas they were constant throughout the entire range of BMI in the controls. DHEAS levels were positively associated with BMI in the PCOS group (P < 0.05) and negatively in the controls (P < 0.01). Measures of upper body fat were related to testosterone and FAI levels, independent of BMI.

CONCLUSIONS

Lower FSH levels were found in women with PCOS than during the early follicular phase of normally ovulating women, suggesting a role in anovulation in PCOS. Obesity itself exerted effects on endocrine variables, with the net result of a reduced LH/FSH ratio and lower serum levels of androstenedione and SHBG in both groups; obesity was associated with increased levels of DHEAS, testosterone and FAI exclusively in the women with PCOS. The results underline the endocrine impact of obesity and body fat distribution and the necessity of applying reference values of BMI matched subjects when establishing the endocrine profile of women with PCOS.

A comparative study of three ovulation induction protocols in polycystic ovarian disease patients in an in vitro fertilization/embryo transfer program

PURPOSE

This study compares the results of three ovulation induction protocols in polycystic ovarian disease (PCOD) patients undergoing an in vitro fertilization-embryo transfer (IVF-ET) program. A total of 85 cycles was studied. The patients were treated with clomiphene citrate (CC) plus human menopausal gonadotropin (hMG) (CC/hMG group), with purified menofollitropin (pFSH) plus hMG (pFSH/hMG group), and with pFSH/hMG plus gonadotropin releasing hormone analogue (GnRH-a) (analogue group). In the analogue group the suppression of luteinizing hormone (LH) with GnRH-a decreased the number of follicles < 12 mm on the day of human chorionic gonadotropin (hCG) administration and the number and percentage of immature oocytes retrieved and increased the percentage of mature oocytes retrieved.

RESULTS

However, fertilization rates of oocytes, cleaved embryo rates, pregnancy rates following replacement, and pregnancy outcomes were not different.

CONCLUSION

Although the suppression of the hypothalamic-pituitary-ovarian axis with GnRH-a in PCOD patients improved follicular synchrony and oocyte maturity, none of the ovulation induction protocols was superior to the others with respect to pregnancy rates and pregnancy outcomes.

Vaginal progesterone administration in physiological doses normalizes raised luteinizing hormone levels in patients with polycystic ovarian syndrome

A raised luteinizing hormone (LH) level is a typical finding in the polycystic ovarian syndrome (PCOS). This inappropriate elevation of LH is thought to interfere with normal follicular development and ovulation. The resulting chronic anovulation is associated with the absence of the luteal phase increase in secretion of progesterone and inhibin. Progesterone can exert both a positive and negative feedback action on LH secretion, but inhibition is thought to occur following prolonged exposure to progesterone. Therefore, the aim of this study was to see if exogenously administered progesterone in physiological doses would normalize circulating LH concentrations in patients with PCOS. Vaginal progesterone was administered twice daily in a dose of 100 mg, at 12 h intervals, to ten women with PCOS. Serum samples were taken on alternate days for radioimmunoassay of follicle stimulating hormone (FSH), LH, estradiol, progesterone and inhibin. To determine the effect of progesterone on LH secretory dynamics in PCOS, LH pulse studies were carried out prior to treatment, and on day 10 of progesterone administration in four of the ten subjects. Mean serum progesterone concentrations reached 51 nmol/l by 4 days after exogenous progesterone treatment, and remained in the mid-luteal phase range, as established in 12 normal cycles, during the use of the vaginal suppository. The mean serum LH concentration had fallen significantly (p < or = 0.01) after 8 days of treatment, and continued to fall progressively until the end of progesterone administration. Serum LH concentrations had fallen into the normal follicular phase range by 14 days (mean 5.5, range 3.4-10.9 IU/l; normal follicular phase range 1.8-10.0 IU/l).(ABSTRACT TRUNCATED AT 250 WORDS)

Cystogenesis of the ovarian antral follicle of the rat: ultrastructural changes and hormonal profile following the administration of dehydroepiandrosterone

Immature 27-day-old female Sprague-Dawley rats were administered daily subcutaneous injections of dehydroepiandrosterone (DHEA, 5 mg/100 g BW) to induce the formation of ovarian follicular cysts. Groups of rats were killed on days 0, 10, 15, 20, 25, and 30. Ovaries from each group of rats were processed for light and electron microscopy and for follicular or cystic fluid hormone analysis. Normal antral follicle fluid, PMSG-treated preovulatory follicular fluid, and cystic fluids were analyzed for progesterone (P), estrone (E1), estradiol (E2), testosterone (T), delta 4-androstenedione (delta 4-A), 5 alpha-dihydrotestosterone (DHT), luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin (PRL). DHEA induced anovulation, acyclicity, and the formation of follicular cysts. In certain antral follicles, there was a dramatic increase in the quantities of smooth endoplasmic reticulum (SER) in the granulosa cells and many mitochondria had tubular cristae. Further depletion of granulosa cell number was associated with intense blebbing of the cytoplasm into the follicle antrum. Formation of the ovarian follicular cyst was completed when the entire cyst was lined by a single layer of transformed granulosa cells in contact via adhering, gap, and tight junctions. These cells had little cytoplasm, mitochondria with lamellar cristae, vast basal and apical bands of microfilaments, and an extensive array of smooth-surfaced endocytotic invaginations on the basal plasma membrane. These endocytotic pits may subsequently form smooth-surfaced vesicles and thereby serve as one mechanism for moving fluid from the ovarian interstitium into the cyst. Theca interna cells were rarely observed in the peripheral regions of the cyst. Abundant smooth muscle cells were located beneath the basement membrane of the epithelial cells comprising the cyst wall. These acquired morphological and physiological features may ensure persistence of the ovarian cyst and thus potentiate a chronic pathological condition. In this study it was also shown that progesterone, estrone, and estradiol as well as androgen concentration increased in the follicle after PMSG treatment. With DHEA treatment, the follicular cystic fluid concentrations of these steroids progressively increased to extremely high levels concurrent with the development of the follicular cysts.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of gonadotropin-releasing hormone agonist on the ovarian response and in vitro fertilization results in polycystic ovarian syndrome: a prospective study

OBJECTIVE

To assess the effect of gonadotropin-releasing hormone agonist (GnRH-a) on pituitary suppression, subsequent ovarian response, and results of in vitro fertilization (IVF) treatments in polycystic ovarian syndrome (PCOS) patients.

DESIGN

Randomized prospective study.

SETTING

In vitro fertilization program and endocrinologic institute.

PATIENTS

Thirty patients with PCOS; 16 received GnRH-a, and 14 did not receive GnRH-a.

INTERVENTIONS

Ovum pick-up and embryo transfer.

MAIN OUTCOME MEASURES

Response to GnRH-a test, serum and follicular fluid (FF) hormonal measurements, steroid levels, and aromatse activity in granulosa cell (GC) culture, and results of IVF.

RESULTS

Pituitary responsiveness was abolished in all patients 14 days after GnRH-a administration, and early luteinization was prevented. Steroid levels in FF did not differ between the two groups. In GC culture, progesterone (P) levels were higher in patients without the GnRH-a (3,704 +/- 1,232 nmol/L versus 2,117 +/- 235 nmol/L; P less than 0.05) as were androstenedione (A) levels (5.3 +/- 1.0 nmol/L versus less than 3.5 nmol/L; P less than 0.05). However, aromatase activity and IVF results were similar in the two groups.

CONCLUSIONS

Administration of GnRH-a in patients with PCOS decreases P and A production by the GC cells and prevents early luteinization. It does not affect the IVF results.

Three types of polycystic ovarian syndrome in relation to androgenic function

OBJECTIVE

To re-evaluate the concept of polycystic ovarian syndrome (PCOS) in view of androgenic function.

DESIGN

Patients were studied endocrinologically and ultrasonographically.

SETTING

This study was performed as a clinical investigation.

PATIENTS, PARTICIPANTS

Sixty-nine euprolactinemic anovulatory patients with luteinizing hormone (LH) hypersecretion and 18 normal volunteers were selected.

INTERVENTIONS

One hundred micrograms of LH-releasing hormone were administered.

MAIN OUTCOME MEASURE(S)

It was possible to divide PCOS patients into three types.

RESULTS

Patients with neither hirsutism nor elevation of serum androstenedione (delta 4) and/or testosterone (T) were designated as type I PCOS (n = 20). Patients without hirsutism but with elevated delta 4 and/or T were referred to as type II PCOS (n = 33). Patients with both hirsutism and elevation of delta 4 and/or T were defined as type III PCOS (n = 16). Concentrations of delta 4 appeared gradedly increasing in types I, II, and III in that order, whereas T concentrations were significantly higher in types II and III than in control. Ultrasonographically, cystic ovaries were found in 88%, 84%, and 100% of types I, II, and III patients, respectively.

CONCLUSIONS

It is postulated that each type may represent a subset of whole spectrum of PCOS from Stein-Leventhal syndrome to simple anovulation with LH hypersecretion.

Endometrial carcinoma; ovarian dysfunction--a risk factor in young women

From a referral area comprising one-fifth of the Swedish female population we investigated possible risk factors for endometrial cancer (EC) in different age groups. Seventy-seven women aged 31-45 with EC were collected retrospectively, and 99 women aged 46-65 were consecutively collected. Both groups were compared to referents randomly selected from a population based study from the city of Göteborg. The referents consisted of 1746 women aged 39-65 years. All cases were studied by hospital record and 82% of the women aged 31-45 years and 85% of those aged 46-65 years were studied by an extensive questionnaire. Among the referents 1409 (81%) were investigated by the above-mentioned questionnaire. Hirsutism, increased body mass index (BMI) and hypertension were significantly more common in both EC groups compared to referents. Nulliparity and infertility were significantly more common in the young EC group. Referents used combined oral contraceptives significantly more often than women developing EC. There was, however, no difference between the groups with respect to the duration of medication with combined oral contraceptives. There was a significant negative correlation between cigarette smoking and the development of EC. These findings indicate that untreated ovarian dysfunction like that present in polycystic ovarian disease (PCO) with unopposed estrogen action on the endometrium is associated with EC in younger women, and that smoking may protect against EC by an 'anti-estrogenic' effect.

Interactions between insulin and insulin-like growth factor I in the pathogenesis of polycystic ovarian disease

Concentrations of growth factors were examined in 28 patients with clinical and endocrinologic signs of polycystic ovarian disease (PCOD). Elevated levels of total insulin-like growth factor I (IGF-I) and decreased levels of the human growth hormone (HGH) were found. Studies of carbohydrate metabolism and of insulin receptors on erythrocytes indicated insulin resistance in all PCOD patients. Elevated insulin and IGF-I levels seem to play a pathogenetic role in PCOD by influencing the development and steroid production of ovarian follicles. Interactions between insulin and IGF-I could be shown at different levels. A positive correlation between elevated insulin and IGF-I concentrations was demonstrated in patients with different classes of gestational diabetes. Hyperinsulinemia seems to be the trigger mechanism and therefore the key to the pathogenetic loop of polycystic ovarian disease.

Oestrogen and androgen states in oligo-amenorrhoeic women with polycystic ovaries

Oestrogen and androgen states have been studied in relation to ovarian morphology defined by ultrasonography in 65 women with oligo-amenorrhoea. Of the 48 women with polycystic ovaries (PCO), 44 (92%) had a withdrawal bleed following progestogen challenge (indicating oestrogenization) compared with just three (18%) of the 17 with non-PCO (P less than 0.001). Median serum concentrations of oestradiol and oestrone were statistically significantly higher in the PCO group but the ranges overlapped widely. Of the four women with PCO but oestrogen deficiency, two were hirsute and had evidence of a severe form of the disorder. The other two were not hirsute and appeared to have hypothalamic dysfunction associated with weight loss overriding the disorder due to pre-existing PCO. Compared with the non-PCO group, the PCO subgroup without hirsutism (n = 31) had statistically significantly higher median values of LH, testosterone, androstenedione, and dehydroepiandrosterone sulphate concentrations, and free androgen index. Concentrations of androgen, but not LH, were significantly higher still in the PCO subgroup with hirsutism (n = 17).

The diagnosis of polycystic ovaries in women with oligo-amenorrhoea: predictive power of endocrine tests

The ability of several endocrine tests to distinguish between women with and without polycystic ovaries (PCO) has been studied prospectively in a series of 65 patients with functional oligo-amenorrhoea using ultrasonography as a reference test. In terms of overall diagnostic accuracy, the free androgen index (FAI) (94%) and the progestogen challenge (89%) gave similar results (Cl = -5 to 15%) but both were significantly better than all the other tests including measurement of serum LH (69%), total testosterone (71%) and androstenedione (74%) (minimum Cl = 6 to 23%). The FAI together with LH measurement was the most accurate of the combinations (97%) but this was not significantly better than the best of the combinations incorporating the progestogen challenge (92%; Cl = -3% to 13%). Given the limited availability of the assay for SHBG, these results show that assessment of oestrogen state is a useful method for categorizing patients with functional oligo-amenorrhoea.