Polycystic ovary syndrome: etiology, pathogenesis and diagnosis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age, with a prevalence of up to 10%. Various diagnostic criteria have been proposed, generally centered around the features of hyperandrogenism and/or hyperandrogenemia, oligo-ovulation and polycystic ovarian morphology. Insulin resistance is present in a majority of cases, with compensatory hyperinsulinemia contributing to hyperandrogenism via stimulation of ovarian androgen secretion and inhibition of hepatic sex hormone-binding globulin production. Adipose tissue dysfunction has been implicated as a contributor to the insulin resistance observed in PCOS. Environmental and genetic factors also have a role in the development of PCOS. The syndrome is associated with numerous morbidities, including infertility, obstetrical complications, type 2 diabetes mellitus, cardiovascular disease, and mood and eating disorders. Despite these morbidities, PCOS may be common in our society owing to evolutionary advantages of the syndrome in ancient times, including smaller family sizes, reduced exposure to childbirth-related mortality, increased muscle mass and greater capacity to store energy. The diagnosis of PCOS hinges on establishing key features while ruling out other hyperandrogenic or oligo-ovulatory disorders. Treatment is focused on the goals of ameliorating hyperandrogenic symptoms, inducing ovulation and preventing cardiometabolic complications.

Lifestyle changes in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) affects 4% to 18% of reproductive-aged women and is associated with reproductive, metabolic and psychological dysfunction. Obesity worsens the presentation of PCOS and weight management (weight loss, maintenance or prevention of excess weight gain) is proposed as an initial treatment strategy, best achieved through lifestyle changes incorporating diet, exercise and behavioural interventions.

OBJECTIVES

To assess the effectiveness of lifestyle treatment in improving reproductive, anthropometric (weight and body composition), metabolic and quality of life factors in PCOS.

SEARCH STRATEGY

Electronic databases (Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE, PsycINFO, CINAHL, AMED), controlled trials register, conference abstracts, relevant journals, reference lists of relevant papers and reviews and grey literature databases, with no language restrictions applied.

SELECTION CRITERIA

Randomised controlled trials comparing lifestyle treatment (diet, exercise, behavioural or combined treatments) to minimal or no treatment in women with PCOS.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, assessed methodological quality and risk of bias and extracted data.

MAIN RESULTS

Six studies were included. Three studies compared physical activity to minimal dietary and behavioural advice or no advice. Three studies compared combined dietary, exercise and behavioural interventions to minimal intervention. There were no studies assessing fertility primary outcomes and no data for meta-analysis on ovulation or menstrual regularity. For secondary outcomes, lifestyle intervention provided benefits when compared to minimal treatment for endpoint values for total testosterone (mean difference (MD) -0.27 nmol/L, 95% confidence interval (CI) -0.46 to -0.09, P = 0.004), hirsutism by the Ferriman-Gallwey score (MD -1.19, 95% CI -2.35 to -0.03, P = 0.04), weight (MD -3.47 kg, 95% CI -4.94 to -2.00, P < 0.00001), waist circumference (MD -1.95 cm, 95% CI -3.34 to -0.57, P = 0.006), waist to hip ratio (MD -0.04, 95% CI -0.07 to -0.00, P = 0.02), fasting insulin (MD -2.02 µU/mL, 95% CI -3.28 to -0.77, P = 0.002) and oral glucose tolerance test insulin (standardised mean difference -1.32, 95% CI -1.73 to -0.92, P < 0.00001) and per cent weight change (MD -7.00%, 95% CI -10.1 to -3.90, P < 0.00001). There was no evidence of effect of lifestyle for body mass index, free androgen index, sex hormone binding globulin, glucose or lipids; and no data for quality of life, patient satisfaction or acne.

AUTHORS' CONCLUSIONS

Lifestyle intervention improves body composition, hyperandrogenism (high male hormones and clinical effects) and insulin resistance in women with PCOS. There was no evidence of effect for lifestyle intervention on improving glucose tolerance or lipid profiles and no literature assessing clinical reproductive outcomes, quality of life and treatment satisfaction.

Extra- and intra-ovarian factors in polycystic ovary syndrome: impact on oocyte maturation and embryo developmental competence

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common metabolic dysfunction and heterogeneous endocrine disorder in women of reproductive age. Although patients with PCOS are typically characterized by increased numbers of oocytes retrieved during IVF, they are often of poor quality, leading to lower fertilization, cleavage and implantation rates, and a higher miscarriage rate.

METHODS

For this review, we searched the database MEDLINE (1950 to January 2010) and Google for all full texts and/or abstract articles published in English with content related to oocyte maturation and embryo developmental competence.

RESULTS

The search showed that alteration of many factors may directly or indirectly impair the competence of maturating oocytes through endocrine and local paracrine/autocrine actions, resulting in a lower pregnancy rate in patients with PCOS. The extra-ovarian factors identified included gonadotrophins, hyperandrogenemia and hyperinsulinemia, although intra-ovarian factors included members of the epidermal, fibroblast, insulin-like and neurotrophin families of growth factors, as well as the cytokines.

CONCLUSIONS

Any abnormality in the extra- and/or intra-ovarian factors may negatively affect the granulosa cell-oocyte interaction, oocyte maturation and potential embryonic developmental competence, contributing to unsuccessful outcomes for patients with PCOS who are undergoing assisted reproduction.

Obesity and polycystic ovary syndrome: association with androgens, leptin and its genotypes

Obesity and hyperandrogenaemia are key features of polycystic ovary syndrome (PCOS). The aim of this study was to investigate whether leptin and androgens are associated with obesity in PCOS subjects and identify whether there exist any genetic alterations in leptin gene in women with PCOS. The results reveal that leptin levels are elevated in women with PCOS and associate with BMI. However, irrespective of the obesity status leptin levels are higher in PCOS cases indicating that increased BMI/obesity may not be the only factor contributing to elevated levels of leptin. With regard to testosterone and androstenedione, the levels were increased in obese individuals irrespective of PCOS status. No correlation between leptin and androstenedione or testosterone was observed in controls and PCOS subjects. The single-nucleotide polymorphism G19A detected in the untranslated exon 1 of leptin gene was not associated with PCOS and does not contribute to elevated levels of leptin. The results overall suggest that androgen and leptin levels are increased in PCOS and obesity. It demonstrates that obesity is a confounding factor for hyperandrogenaemia irrespective of their PCOS status. The study rules out role of obesity status and leptin genotype in increase in leptin levels observed in PCOS cases.

Cholesterol, endocrine and metabolic disturbances in sporadic anovulatory women with regular menstruation

BACKGROUND

Sporadic anovulation among regularly menstruating women is not well understood. It is hypothesized that cholesterol abnormalities may lead to hormone imbalances and incident anovulation. The objective was to evaluate the association between lipoprotein cholesterol levels and endocrine and metabolic disturbances and incident anovulation among ovulatory and anovulatory women reporting regular menstruation.

METHODS

The BioCycle Study was a prospective cohort study conducted at the University at Buffalo from September 2005 to 2007, which followed 259 self-reported regularly menstruating women aged 18-44 years, for one or two complete menstrual cycles. Sporadic anovulation was assessed across two menstrual cycles.

RESULTS

Mean total and low-density lipoprotein cholesterol and triglycerides levels across the menstrual cycles were higher during anovulatory cycles (mean difference: 4.6 (P = 0.01), 3.0 (P = 0.06) and 6.4 (P = 0.0002) mg/dl, respectively, adjusted for age and BMI). When multiple total cholesterol (TC) measures prior to expected ovulation were considered, we observed a slight increased risk of anovulation associated with increased levels of TC (odds ratio per 5 mg/dl increase, 1.07; 95% confidence interval, 0.99, 1.16). Sporadic anovulation was associated with an increased LH:FSH ratio (P = 0.002), current acne (P = 0.02) and decreased sex hormone-binding globulin levels (P = 0.005).

CONCLUSIONS

These results do not support a strong association between lipoprotein cholesterol levels and sporadic anovulation. However, sporadic anovulation among regularly menstruating women is associated with endocrine disturbances which are typically observed in women with polycystic ovary syndrome.

The polycystic ovary post-rotterdam: a common, age-dependent finding in ovulatory women without metabolic significance

INTRODUCTION

The age-specific prevalence of polycystic ovaries (PCO), as defined by the Rotterdam criteria, among normal ovulatory women, has not yet been reported. It is also uncertain whether these women differ from their peers in the hormonal or metabolic profile.

METHODS

A total of 262 ovulatory Caucasian women aged 25-45 yr, enrolled in a community-based ovarian aging study (OVA), underwent transvaginal ultrasound assessment of ovarian volume and antral follicle count (AFC) in the early follicular phase and were categorized as to whether they met the Rotterdam definition of PCO by AFC (≥12 in one ovary) and/or by volume (>10 cm(3) for one ovary). The effect of age on prevalence of PCO was assessed. Serum hormones and metabolic measures were compared between women meeting each element of the Rotterdam criterion and those without PCO using age-adjusted linear regressions.

RESULTS

The prevalence of PCO by AFC was 32% and decreased with age. Those with PCO by AFC had lower FSH; higher anti-Müllerian hormone, estrone, dehydroepiandrostenedione sulfate, and free androgen index; and slightly higher total testosterone than those without PCO. However, slightly higher body mass index and waist circumference were the only metabolic differences. Women with PCO by volume had higher anti-Müllerian hormone and free androgen index but did not differ in any other hormonal or metabolic parameter.

DISCUSSION

PCO is a common, age-dependent finding among ovulatory women. These women lack the metabolic abnormalities seen in PCO syndrome. Isolated PCO in an ovulatory woman is not an indication for metabolic evaluation.

Exercise therapy in polycystic ovary syndrome: a systematic review

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder, affecting 8-12% of women. Lifestyle modification, including increased physical activity, is the first-line approach in managing PCOS. A systematic review was performed to identify and describe the effect of exercise as an independent intervention on clinical outcomes in PCOS.

METHODS

Five databases were searched with no time limit. A pre-specified definition of PCOS was not used. Studies were included if exercise therapy (aerobic and/or resistance) could be evaluated as an independent treatment against a comparison group. Outcomes measured included cardiovascular risk factors [insulin resistance (IR), lipid profiles, blood pressure and weight] and reproductive measures (ovulation, menstrual regularity and fertility outcomes). Quality analysis was performed based on the Cochrane Handbook of Systematic Reviews and the Quality of Reporting of Meta-Analyses checklist.

RESULTS

Eight manuscripts were identified (five randomized controlled trials and three cohort studies). All studies involved moderate intensity physical activity and most were of either 12 or 24 weeks duration with frequency and duration of exercise sessions ranging between studies. The most consistent improvements included improved ovulation, reduced IR (9-30%) and weight loss (4.5-10%). Improvements were not dependant on the type of exercise, frequency or length of exercise sessions.

CONCLUSIONS

Exercise-specific interventions in PCOS are limited. Studies vary considerably in design, intensity and outcome measures; therefore conclusive results remain elusive. Larger, optimally designed studies are needed to both gain insights into the mechanisms of exercise action and to evaluate the public health impact of exercise of PCOS.

Cardiovascular risk factors in polycystic ovary syndrome

A total of 31 women with polycystic ovary syndrome (PCOS) and 31 healthy age/body mass index matched controls were compared for serum hormones, basal and oral-glucose stimulated glucose, insulin, homocysteine, high sensitive C-reactive protein (hsCRP) and lipid levels. The women with PCOS had significantly higher serum fasting insulin, homocysteine, total cholesterol and LDL cholesterol level than controls, whereas no differences were detected in serum fasting or OGTT 60th- and 120th-minute glucose concentrations, hsCRP, HDL cholesterol, VLDL cholesterol and triglyceride levels between PCOS and control women. Insulin resistance was found in 54.8% (17/31) of PCOS patients by glucose: insulin (G/I) ratio, whereas only 29.0% (9/31) of control women (p = 0.04). Multivariate linear regression analysis revealed that only waist/hip ratio was independent determinants of G/I ratio. PCOS is associated with some biochemical and clinical risk factors for cardiovascular disease. Therefore, patients with PCOS should undergo comprehensive evaluation for recognised cardiovascular risk factors.

Polycystic ovary syndrome: a complex condition with psychological, reproductive and metabolic manifestations that impacts on health across the lifespan

Polycystic ovary syndrome (PCOS) is of clinical and public health importance as it is very common, affecting up to one in five women of reproductive age. It has significant and diverse clinical implications including reproductive (infertility, hyperandrogenism, hirsutism), metabolic (insulin resistance, impaired glucose tolerance, type 2 diabetes mellitus, adverse cardiovascular risk profiles) and psychological features (increased anxiety, depression and worsened quality of life). Polycystic ovary syndrome is a heterogeneous condition and, as such, clinical and research agendas are broad and involve many disciplines. The phenotype varies widely depending on life stage, genotype, ethnicity and environmental factors including lifestyle and bodyweight. Importantly, PCOS has unique interactions with the ever increasing obesity prevalence worldwide as obesity-induced insulin resistance significantly exacerbates all the features of PCOS. Furthermore, it has clinical implications across the lifespan and is relevant to related family members with an increased risk for metabolic conditions reported in first-degree relatives. Therapy should focus on both the short and long-term reproductive, metabolic and psychological features. Given the aetiological role of insulin resistance and the impact of obesity on both hyperinsulinaemia and hyperandrogenism, multidisciplinary lifestyle improvement aimed at normalising insulin resistance, improving androgen status and aiding weight management is recognised as a crucial initial treatment strategy. Modest weight loss of 5% to 10% of initial body weight has been demonstrated to improve many of the features of PCOS. Management should focus on support, education, addressing psychological factors and strongly emphasising healthy lifestyle with targeted medical therapy as required. Monitoring and management of long-term metabolic complications is also an important part of routine clinical care. Comprehensive evidence-based guidelines are needed to aid early diagnosis, appropriate investigation, regular screening and treatment of this common condition. Whilst reproductive features of PCOS are well recognised and are covered here, this review focuses primarily on the less appreciated cardiometabolic and psychological features of PCOS.

Assessment of cardiovascular risk and prevention of cardiovascular disease in women with the polycystic ovary syndrome: a consensus statement by the Androgen Excess and Polycystic Ovary Syndrome (AE-PCOS) Society

OBJECTIVE

Women with polycystic ovary syndrome (PCOS) often have cardiovascular disease (CVD) risk factors. The Androgen Excess and Polycystic Ovary Syndrome (AE-PCOS) Society created a panel to provide evidence-based reviews of studies assessing PCOS-CVD risk relationships and to develop guidelines for preventing CVD.

PARTICIPANTS

An expert panel in PCOS and CVD reviewed literature and presented recommendations.

EVIDENCE

Only studies comparing PCOS with control patients were included. All electronic databases were searched; reviews included individual studies/databases, systematic reviews, abstracts, and expert data. Articles were excluded if other hyperandrogenic disorders were not excluded, PCOS diagnosis was unclear, controls were not described, or methodology precluded evaluation. Inclusion/exclusion criteria were confirmed by at least two reviewers and arbitrated by a third.

CONSENSUS PROCESS

Systematic reviews of CVD risk factors were compiled and submitted for approval to the AE-PCOS Society Board.

CONCLUSIONS

Women with PCOS with obesity, cigarette smoking, dyslipidemia, hypertension, impaired glucose tolerance, and subclinical vascular disease are at risk, whereas those with metabolic syndrome and/or type 2 diabetes mellitus are at high risk for CVD. Body mass index, waist circumference, serum lipid/glucose, and blood pressure determinations are recommended for all women with PCOS, as is oral glucose tolerance testing in those with obesity, advanced age, personal history of gestational diabetes, or family history of type 2 diabetes mellitus. Mood disorder assessment is suggested in all PCOS patients. Lifestyle management is recommended for primary CVD prevention, targeting low-density and non-high-density lipoprotein cholesterol and adding insulin-sensitizing and other drugs if dyslipidemia or other risk factors persist.

Ovarian function and obesity--interrelationship, impact on women's reproductive lifespan and treatment options

Insulin resistance (IR) is a consequence of obesity, and in women it is often inextricably linked with ovarian function leading to clinical reproductive manifestations such as early menarche onset, subfertility and polycystic ovary syndrome (PCOS). Likewise, the dramatic fall in oestrogen production after menopause may contribute to weight gain and changes in adipose tissue distribution. Overall, women who are obese, especially those with reproductive complications including PCOS, have been identified as specific high risk subgroups for further progression through to prediabetes, type 2 diabetes mellitus (T2DM) and potentially cardiovascular disease (CVD). This review focuses on the interrelationship between the ovarian function and obesity as well as its treatment strategies.

Efficient derivation of Chinese human embryonic stem cell lines from frozen embryos

Human embryonic stem (hES) cells are pluripotent cells derived from the inner cell mass of blastocysts. Their unique properties of self-renewal and pluripotency make them an attractive tool for basic research as well as a potential cell resource for therapy. However, each hES cell line demonstrates different identity. It is desirable to obtain more fully characterized hES cell lines with newly developed technologies associated with hES cell culture. Here, we report our experience of efficient derivation of three new Chinese hES cell lines (SHhES2, SHhES3, and SHhES4) from in vitro fertilization discarded embryos donated by women with polycystic ovary syndrome. These cell lines were derived under conditions minimizing exposure to animal components and maintained at an undifferentiated state for long-term culture. They retained a normal karyotype and expressed ALP, OCT4, SOX2, SSEA-4, TRA-1-60 and TRA-1-81. RT-PCR analysis also revealed high expression levels of pluripotency markers such as OCT4, LEFTY A, SOX2, TDGF-1, THY1, FGF4, NANOG, and REX1. When suspended in low-attachment culture dishes, embryoid bodies formed and were comprised of various differentiated cell types from all three embryonic germ layers. However, well-shaped teratomas were only harvested from line SHhES2, not from SHhES3 and SHhES4, indicating that the differentiation ability in vivo differs among the three cell lines. Collectively, the three new hES cell lines were established and fully characterized. The effort paves the way toward generating hES cell lines without contamination by animal components. All of these cell lines are available by contact Ying Jin at yjin@sibs.ac.cn.

Impaired glucose tolerance, type 2 diabetes and metabolic syndrome in polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND Polycystic ovary syndrome (PCOS) is a common condition in reproductive-aged women associated with impaired glucose tolerance (IGT), type 2 diabetes mellitus (DM2) and the metabolic syndrome. METHODS A literature search was conducted (MEDLINE, CINAHL, EMBASE, clinical trial registries and hand-searching) identifying studies reporting prevalence or incidence of IGT, DM2 or metabolic syndrome in women with and without PCOS. Data were presented as odds ratio (OR) [95% confidence interval (CI)] with fixed- and random-effects meta-analysis by Mantel-Haenszel methods. Quality testing was based on Newcastle-Ottawa Scaling and The Cochrane Collaboration's risk of bias assessment tool. Literature searching, data abstraction and quality appraisal were performed by two investigators. RESULTS A total of 2192 studies were reviewed and 35 were selected for final analysis. Women with PCOS had increased prevalence of IGT (OR 2.48, 95% CI 1.63, 3.77; BMI-matched studies OR 2.54, 95% CI 1.44, 4.47), DM2 (OR 4.43, 95% CI 4.06, 4.82; BMI-matched studies OR 4.00, 95% CI 1.97, 8.10) and metabolic syndrome (OR 2.88, 95% CI 2.40, 3.45; BMI-matched studies OR 2.20, 95% CI 1.36, 3.56). One study assessed IGT/DM2 incidence and reported no significant differences in DM2 incidence (OR 2.07, 95% CI 0.68, 6.30). One study assessed conversion from normal glucose tolerance to IGT/DM2 (OR 2.4, 95% CI 0.7, 8.0). No studies reported metabolic syndrome incidence. CONCLUSIONS Women with PCOS had an elevated prevalence of IGT, DM2 and metabolic syndrome in both BMI and non-BMI-matched studies. Few studies have determined IGT/DM2 or metabolic syndrome incidence in women with and without PCOS and further research is required.

Serum antimullerian hormone (AMH) levels are elevated in adolescent girls with polycystic ovaries and the polycystic ovarian syndrome (PCOS)

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder in adolescents, with potentially significant lifelong consequences. This prospective study set out to determine if the investigators could derive a threshold value of antimullerian hormone (AMH) that would predict its presence according to two internationally recognized definitions using a simple measurement, avoiding more extensive and potentially more invasive investigations. The study failed to demonstrate, in a general adolescent population, that serum AMH is a reliable predictor of PCO morphology or for the presence of PCOS.