Polycystic ovary syndrome

 Polycystic ovary syndrome

Polycystic ovary syndrome, or PCOS, is the most common endocrine disorder in women of reproductive age. The syndrome is named after the characteristic cysts which may form on the ovaries, though it is important to note that this is a sign and not the underlying cause of the disorder.

Women with PCOS may experience irregular menstrual periods, heavy periods, excess hair, acne, pelvic pain, difficulty getting pregnant, and patches of thick, darker, velvety skin. The primary characteristics of this syndrome include: hyperandrogenism, anovulation, insulin resistance, and neuroendocrine disruption.

A review of the international evidence found that the prevalence of PCOS could be as high as 26% among some populations, though ranges between 4% and 18% are reported for general populations. Despite its high prevalence, the exact cause of PCOS remains uncertain and there is no known cure.

Two definitions are commonly used:

NIH

In 1990 a consensus workshop sponsored by the NIH/NICHD suggested that a person has PCOS if they have all of the following:

oligoovulation

signs of androgen excess (clinical or biochemical)

exclusion of other disorders that can result in menstrual irregularity and hyperandrogenism

Rotterdam

In 2003 a consensus workshop sponsored by ESHRE/ASRM in Rotterdam indicated PCOS to be present if any 2 out of 3 criteria are met, in the absence of other entities that might cause these findings:

oligoovulation and/or anovulation

excess androgen activity

polycystic ovaries (by gynecologic ultrasound)

The Rotterdam definition is wider, including many more women, the most notable ones being women without androgen excess. Critics say that findings obtained from the study of women with androgen excess cannot necessarily be extrapolated to women without androgen excess.

Androgen Excess PCOS Society

In 2006, the Androgen Excess PCOS Society suggested a tightening of the diagnostic criteria to all of the following:

excess androgen activity

oligoovulation/anovulation and/or polycystic ovaries

exclusion of other entities that would cause excess androgen activity

Signs and symptoms

Signs and symptoms of PCOS include irregular or no menstrual periods, heavy periods, excess body and facial hair, acne, pelvic pain, difficulty getting pregnant, and patches of thick, darker, velvety skin. This metabolic, endocrine and reproductive disorder is not universally defined, but the most common symptoms are irregular or irregular absent periods, ovarian cysts, enlarged ovaries, excess androgen, weight gain and hirsutism. Associated conditions include type 2 diabetes, obesity, obstructive sleep apnea, heart disease, mood disorders, and endometrial cancer. This disease is related to the number of follicles per ovary each month growing from the average range of 6 to 8 to double, triple or more. it is important to distinguish between PCOS (the syndrome) and a woman with PCO (polycystic ovaries): to have PCOS, a woman must have at least two of these three symptoms (PCO, anovulation/oligoovulation and hyperandrogenism). This means that a woman can have PCOS (displaying anovulation and hyperandrogenism) without having PCO. At the same time, having polycystic ovaries does not relate necessary with the presence of PCOS.

Further information: Infertility in polycystic ovary syndrome

Common signs and symptoms of PCOS include the following:

Menstrual disorders: PCOS mostly produces oligomenorrhea (fewer than nine menstrual periods in a year) or amenorrhea (no menstrual periods for three or more consecutive months), but other types of menstrual disorders may also occur.

Infertility: This generally results directly from chronic anovulation (lack of ovulation).

High levels of masculinizing hormones: Known as hyperandrogenism, the most common signs are acne and hirsutism (male pattern of hair growth, such as on the chin or chest), but it may produce hypermenorrhea (heavy and prolonged menstrual periods), androgenic alopecia (increased hair thinning or diffuse hair loss), or other symptoms. Approximately three-quarters of women with PCOS (by the diagnostic criteria of NIH/NICHD 1990) have evidence of hyperandrogenemia.

Metabolic syndrome: This appears as a tendency towards central obesity and other symptoms associated with insulin resistance, including low energy levels and food cravings. Serum insulin, insulin resistance, and homocysteine levels are higher in women with PCOS.

Polycystic Ovaries: Ovaries might get enlarged and comprise follicles surrounding the eggs. As result, ovaries might fail to function regularly.

Women with PCOS tend to have central obesity, but studies are conflicting as to whether visceral and subcutaneous abdominal fat is increased, unchanged, or decreased in women with PCOS relative to reproductively normal women with the same body mass index. In any case, androgens, such as testosterone, androstanolone (dihydrotestosterone), and nandrolone decanoate have been found to increase visceral fat deposition in both female animals and women.

Although 80% of PCOS presents in women with obesity, 20% of women diagnosed with the disease are non-obese or "lean" women.[33] However, obese women that have PCOS have a higher risk of adverse outcomes such as, hypertension, insulin resistance, metabolic syndrome, and endometrial hyperplasia.

Even though most women with PCOS are overweight or obese, it is important to acknowledge that non-overweight women can also be diagnosed with PCOS. Up to 30% of women diagnosed with PCOS maintain a normal weight before and after diagnosis. "Lean" women still face the various symptoms of PCOS with the added challenges of getting their symptoms properly addressed and recognized. Lean women often go undiagnosed for years, and usually are diagnosed after struggles to conceive. Lean women are likely to have incidences of missed diagnosis of diabetes and cardiovascular diseases. These women also have an increased risk of developing insulin resistance despite not being overweight. Lean women are often taken less seriously with their diagnosis of PCOS, and also face challenges finding appropriate treatment options. This is because most treatment options are limited to approaches of losing weight and healthy dieting.

Associated conditions

Many individuals aren't under the impression that the first warning sign is usually a change in appearance. But there are also manifestations of mental health problems, such as anxiety, depression, and eating disorders.

A diagnosis of PCOS suggests an increased risk of the following:

Endometrial hyperplasia and endometrial cancer (cancer of the uterine lining) are possible, due to overaccumulation of uterine lining, and also lack of progesterone resulting in prolonged stimulation of uterine cells by estrogen. It is not clear whether this risk is directly due to the syndrome or from the associated obesity, hyperinsulinemia, and hyperandrogenism.

Insulin resistance/Type II diabetes. A review published in 2010 concluded that women with PCOS have an elevated prevalence of insulin resistance and type II diabetes, even when controlling for body mass index (BMI). PCOS also makes a woman at higher risk for diabetes.

High blood pressure, in particular if obese or during pregnancy

Depression and anxiety

Dyslipidemia – disorders of lipid metabolism — cholesterol and triglycerides. Women with PCOS show a decreased removal of atherosclerosis-inducing remnants, seemingly independent of insulin resistance/Type II diabetes.

Cardiovascular disease, with a meta-analysis estimating a 2-fold risk of arterial disease for women with PCOS relative to women without PCOS, independent of BMI.

Strokes

Weight gain

Miscarriage

Sleep apnea, particularly if obesity is present

Non-alcoholic fatty liver disease, particularly if obesity is present

Acanthosis nigricans (patches of darkened skin under the arms, in the groin area, on the back of the neck)[20]

Autoimmune thyroiditis

Some studies report a higher incidence of PCOS among transgender men (prior to taking testosterone),[49][50][51] though not all have not found the same association. People with PCOS in general are also reportedly more likely to see themselves as "sexually undifferentiated" or "androgynous" and "less likely to identify with a female gender scheme."

The risk of ovarian cancer and breast cancer is not significantly increased overall.

Cause

PCOS is caused by a combination of genetic and environmental factors. Risk factors include obesity, a lack of physical exercise, and a family history of someone with the condition. Transgender men may also experience a higher than expected rate of PCOS.Diagnosis is based on two of the following three findings: anovulation, high androgen levels, and ovarian cysts. Cysts may be detectable by ultrasound. Other conditions that produce similar symptoms include adrenal hyperplasia, hypothyroidism, and high blood levels of prolactin.

PCOS is a heterogeneous disorder of uncertain cause. There is some evidence that it is a genetic disease. Such evidence includes the familial clustering of cases, greater concordance in monozygotic compared with dizygotic twins and heritability of endocrine and metabolic features of PCOS. There is some evidence that exposure to higher than typical levels of androgens and the anti-Müllerian hormone (AMH) in utero increases the risk of developing PCOS in later life.

Genetics

The genetic component appears to be inherited in an autosomal dominant fashion with high genetic penetrance but variable expressivity in females; this means that each child has a 50% chance of inheriting the predisposing genetic variant(s) from a parent, and, if a daughter receives the variant(s), the daughter will have the disease to some extent. The genetic variant(s) can be inherited from either the father or the mother, and can be passed along to both sons (who may be asymptomatic carriers or may have symptoms such as early baldness and/or excessive hair) and daughters, who will show signs of PCOS. The phenotype appears to manifest itself at least partially via heightened androgen levels secreted by ovarian follicle theca cells from women with the allele. The exact gene affected has not yet been identified. In rare instances, single-gene mutations can give rise to the phenotype of the syndrome. Current understanding of the pathogenesis of the syndrome suggests, however, that it is a complex multigenic disorder.

Due to the scarcity of large-scale screening studies, the prevalence of endometrial abnormalities in PCOS remains unknown, though women with the condition may be at increased risk for endometrial hyperplasia and carcinoma as well as menstrual dysfunction and infertility.

The severity of PCOS symptoms appears to be largely determined by factors such as obesity. PCOS has some aspects of a metabolic disorder, since its symptoms are partly reversible. Even though considered as a gynecological problem, PCOS consists of 28 clinical symptoms.[citation needed]

Even though the name suggests that the ovaries are central to disease pathology, cysts are a symptom instead of the cause of the disease. Some symptoms of PCOS will persist even if both ovaries are removed; the disease can appear even if cysts are absent. Since its first description by Stein and Leventhal in 1935, the criteria of diagnosis, symptoms, and causative factors are subject to debate. Gynecologists often see it as a gynecological problem, with the ovaries being the primary organ affected. However, recent insights show a multisystem disorder, with the primary problem lying in hormonal regulation in the hypothalamus, with the involvement of many organs. The term PCOS is used due to the fact that there is a wide spectrum of symptoms possible. It is common to have polycystic ovaries without having PCOS; approximately 20% of European women have polcystic ovaries, but most of those women do not have PCOS.

Environment

PCOS may be related to or worsened by exposures during the prenatal period, epigenetic factors, environmental impacts (especially industrial endocrine disruptors, such as bisphenol A and certain drugs) and the increasing rates of obesity. Along with PCOS appearing to be inherited as a complex genetic trait that is characterized by both androgen excess and ovulatory dysfunction.

Endocrine disruptors are defined as chemicals that can interfere with the Endocrine system by mimicking hormones such as estrogen; "they are of particular interest to reproductive health, including PCOS and its related symptoms". However, additional research is needed to assess the role that endocrine disruptors may play in disrupting reproductive health among women and possibly triggering or exacerbating PCOS and its related symptoms.