Insulin Resistance in Polycystic Ovarian Disease

Factors that affect maternal insulin resistance and modify fetal growth and body composition

Fetal growth is multifactorial and can be altered by a variety of extrinsic and intrinsic factors. The maternal, placental, and fetal contribution to growth must all be considered. Of particular interest are maternal metabolic regulation and the availability of nutrients to the developing fetus. Weight gain, hyperlipidemia, and insulin resistance occur as a normal adaptation to pregnancy. Obesity and underlying insulin resistance among women of reproductive age are rapidly increasing, and the contribution of pregnancy on this abnormal metabolic background poses additional maternal and fetal challenges. Many components of the metabolic syndrome have been associated with changes in fetal growth, including obesity, dyslipidemia, hypertension, and insulin resistance or glucose intolerance. Additional factors affect fetal growth and include diet, exercise, and smoking. In this review, we briefly discuss the importance and descriptions of fetal growth, followed by a discussion of several of the extrinsic and intrinsic established factors affecting fetal growth. We highlight factors that may modify fetal growth and body composition directly or indirectly through alterations in maternal metabolism.

First assessment of menstrual cycle function and reproductive endocrine status in Samoan women

BACKGROUND

American Samoa and Samoa are now characterized by one of the world's highest levels of adult overweight and obesity. Our objective was to investigate patterns of menstrual cyclicity reported by Samoan women and examine the relationship to adiposity and select hormone levels.

METHODS

A cross-sectional analysis was performed among Samoan women, aged 18-39 years (n = 322), using anthropometric and biomarker measures of adiposity and reproductive health, including insulin, adiponectin, testosterone, sex hormone-binding globulin, free androgen index (FAI) and mullerian-inhibiting substance (MIS). Menstrual regularity was assessed from self-reported responses. Multivariable models were estimated to adjust for potential confounding of the associations between menstrual patterns and other measures.

RESULTS

A high proportion of the women (13.7%) reported oligomenorrhea or amenorrhea (OM/AM). More than three-quarters, 80.7%, of women were either overweight or obese, using Polynesian-specific criteria, and OM/AM was significantly associated with higher BMI. Abdominal circumference and insulin levels were significantly higher, and adiponectin levels were lower, in those who reported OM/AM versus regular menstruation. The FAI was higher in women with increased BMI. MIS levels declined with age, more slowly in those reporting OM/AM.

CONCLUSIONS

Self-reported OM/AM was associated with an elevated BMI, abdominal adiposity and serum insulin, and with reduced adiponectin levels. These findings support a high rate of metabolic syndrome, and perhaps PCOS and reproductive dysfunction, among Samoan women.

Circulating inflammatory markers in polycystic ovary syndrome: a systematic review and metaanalysis

OBJECTIVE

To perform a review and metaanalysis of the studies evaluating the status of serum inflammatory markers in women with polycystic ovary syndrome (PCOS).

DESIGN

Systematic review and metaanalysis of articles published in English before January 2010 and identified using the PubMed search engine.

SETTING

Academic hospital.

PATIENT(S)

Women with PCOS and appropriate controls.

INTERVENTION(S)

Measurement of serum concentrations of inflammatory markers by high-sensitivity techniques.

MAIN OUTCOME MEASURE(S)

Metaanalyses of the mean difference in serum C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations among patients with PCOS and appropriate controls, applying random-effects models to limit interstudy variability, and using appropriate estimates of evidence dissemination bias.

RESULT(S)

Metaanalysis of the 31 articles meeting inclusion criteria showed that circulating CRP was 96% higher in women with PCOS compared to controls (95% confidence interval, 71%-122%; z = 7.32) without evidence of dissemination bias (Egger's regression intercept, 0.45; 95% confidence interval, -2.30 to 3.21). These findings persisted after excluding five studies with mismatches in body mass, frequency of obesity, or both, between women with PCOS and controls. Metaanalyses involving 10 studies of IL-6, and nine studies of TNF-α revealed no statistically significant differences between PCOS and controls.

CONCLUSION(S)

Women with PCOS exhibit an elevation in circulating CRP that is independent of obesity. This finding corroborates existing molecular evidence of the chronic low-grade inflammation that may underpin the pathogenesis of this disorder.

Metabolic fuel and clinical implications for female reproduction

Reproduction is a physiologically costly process that consumes significant amounts of energy. The physiological mechanisms controlling energy balance are closely linked to fertility. This close relationship ensures that pregnancy and lactation occur only in favourable conditions with respect to energy. The primary metabolic cue that modulates reproduction is the availability of oxidizable fuel. An organism's metabolic status is transmitted to the brain through metabolic fuel detectors. There are many of these detectors at both the peripheral (e.g., leptin, insulin, ghrelin) and central (e.g., neuropeptide Y, melanocortin, orexins) levels. When oxidizable fuel is scarce, the detectors function to inhibit the release of gonadotropin-releasing hormone and luteinizing hormone, thereby altering steroidogenesis, reproductive cyclicity, and sexual behaviour. Infertility can also result when resources are abundant but food intake fails to compensate for increased energy demands. Examples of these conditions in women include anorexia nervosa and exercise-induced amenorrhea. Infertility associated with obesity appears to be less related to an effect of oxidizable fuel on the hypothalamic-pituitary-ovarian axis. Impaired insulin sensitivity may play a role in the etiology of these conditions, but their specific etiology remains unresolved. Research into the metabolic regulation of reproductive function has implications for elucidating mechanisms of impaired pubertal development, nutritional amenorrhea, and obesity-related infertility. A better understanding of these etiologies has far-reaching implications for the prevention and management of reproductive dysfunction and its associated comorbidities.

Pseudotumor cerebri from sinus venous thrombosis, associated with polycystic ovary syndrome and hereditary hypercoagulability

OBJECTIVE

The association of pseudotumor cerebri, visual impairment, hypothyroidism, polycystic ovary syndrome (PCOS), and a hypercoagulable state due to a factor V and a prothrombin mutation has not been reported previously.

CASE REPORT

A 20-year-old obese woman developed menstrual cycle irregularities since age 14 years, initially bitemporal and latter diffuse headache since age 14 years, and bilateral visual impairment, described as sparkling black points. Ophthalmologically there was a recurrent papilledema. Clinical neurologic investigations revealed sore neck muscles and hirsutism. Magnetic resonance imaging of the brain, orbita and cervical spine, and investigations of cerebrospinal fluid were non-informative. Visually evoked potentials revealed demyelination of the optic nerves. Gynecologic investigations revealed PCOS and endocrinologic investigations hypothyroidism and hyperandrogenism. Tests for thrombophilia disclosed a heterozygote state for the G1.697A factor V Leiden and the G20.210A prothrombin mutation. A possible relationship between pseudotumor cerebri and the ophthalmologic, gynecologic, endocrinologic and coagulation abnormalities is discussed.

CONCLUSIONS

For the first time we describe the association of pseudotumor cerebri, optic nerve demyelination, PCOS, other endocrinologic abnormalities, and thrombophilia due to a factor V and prothrombin mutation. A causal relationship between these abnormalities remains elusive.