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This disease is known for more than 100 years, but so far the etiology and pathogenesis of polycystic ovarian disease is not fully clarified. So far there is no universally accepted definition of polycystosis, due to the fact that the disease has multiple manifestations and heterogeneous origin.
By itself, gynecologic ultrasound of ovarian morphology is not a basis for diagnosis PCO. This should be know to women, who tend too easily succumb to the entreaties of the doctors to undergo surgery.
Clinical pattern of polycystosis is largely identical to the clinic of a number of other hormonal disorders - hypothyroidism, hyperprolactinemia, adrenal or ovarian tumors. Therefore, the diagnosis PCO can only be made if there are signs of hyperandrogenism and other its causes have been excluded.
Sometimes doctors rush to make a diagnosis of polycystosis, guided only by the results of ultrasound examination, and prescribe hormones, which in the absence of polycystosis can rather harm than help. Since increasing the ovaries may be due to a variety of reasons, in the presence of only ultrasound data, it is very easily be mistaken.
Therefore, for a correct diagnosis comprehensive examination must be done with determining the levels of male sex hormones, luteinizing hormone and follicle-stimulating hormone that regulate ovarian function. Moreover, the survey should be conducted at least three times - in the first phase of the menstrual cycle, during ovulation and the second phase.
Polycystic ovaries: terminology and diagnosis
In 1990 a consensus workshop in U.S. suggested that a patient has PCO if there are ALL of the following:
1. Iirregularity of the menstrual cycle;
2. Presence of clinical or biochemical signs of androgen excess such as hirsutism
over 8 points on , acne, male pattern baldness or a high level of androgens in the blood serum.
3. Other entities are excluded that would cause polycystic ovaries.
According to this definition, ultrasound is not required for PCO diagnosis. However, in the opinion of many European experts, ultrasound evidence of polycystic ovarian structure is necessary.
According to the latest classification (1997), there are two forms of polycystic ovaries:
- primary or true polycystosis (or PCO disease - PCOD);
- secondary polycystosis (or PCO syndrome - PCOS).
Typical signs of PCO disease are as follows:
- disturbance of menstrual function;
- primary infertility;
- hirsutism.
These symptoms usually occur between the ages of 18 and 25, whereas with PCO syndrome, this clinical pattern is seen in women older than 35 years, and infertility is secondary.
Disturbances of menstrual function observed in 100% of polysistosis, hirsutism - in 54-85% of cases, but it is not considered a major symptom of the disease, as often it may be caused by genetic increased sensitivity of hair follicles to normal androgen levels.
Primary polycystosis occurs in women with normal body weight, and it does not have elevated levels of insulin in the blood. It is a more severe disease and responds poorly to treatment - both conservative and surgical.
Most often the disease begins in girls at puberty. According to many scientists, its development may also be caused by acute respiratory infections, angina, stress, transferred the girl in ten - twelve years, family history, the first and early abortions.
Secondary polycystosis diagnosed in women in middle age, overweight and having high levels of insulin in the blood. It can also develop in the climacteric period, due to ovarian failure. If the body lacks one of hormones this stimulates excess production of its antagonist, which may cause serious deviations in the work of all organs whose function is regulated by these hormones.
Secondary polycystosis (PCOS) is easier to treat, and it can be eliminated even by conservative methods.
Unfortunately, clinicians often confuse the terms "PCOD" and "PCOS", implying in both cases, polycystic ovarian disease. Accordingly, the treatment is directed not to eliminate the causes of the disease, but mainly to normalize hormonal balance, regardless of what the breach is caused.
But here's a big difference. In particular, in secondary polycystosis, surgical intervention is ineffective, and a larger effect can be achieved by conservative methods of treatment. With appropriate treatment (antibiotic, antioxidant, diet therapy, physical therapy) and the elimination of the inflammatory process in the ovaries, the patient's endocrine status can be restored.
To avoid confusion in this matter, in the future I will use the term "PCOS" only when it will go just about secondary polycystosis.
Perhaps because of this confusion and hasty diagnosis, polycystic ovaries are often among the most common gynecological problems in women. In fact, according to the data of 2000, primary polycystosis is about 10-12% in the structure of Gynecologic diseases.
Another thing is that polycystic ovaries is one of the most common causes of infertility in women (estimates vary from 40 to 70 percent).
What is known about the pathogenesis of polycystosis?
Currently the leading theory is the central development of polycystosis, which connects with the pathological state with primary or secondary damage to the hypothalamic centers and, consequently, with impaired secretion of gonadotropin-releasing hormones: luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
Inhibition in production of FSH leads to a deficiency of enzymes in the ovaries, needed for the synthesis of estrogens, leading to accumulation of androgens, which suppress the growth and maturation of follicles and promote their cystic degeneration.
On the other hand, the hyperproduction of LH stimulates the secretion of androgens, which in turn further suppresses the secretion of FSH and production of estrogens in the ovaries.
It is more or less established that the initial impetus to the formation of this neuroendocrine syndrome is given by violation of secretion of neurotransmitters in the brain, which causes a whole chain of failures in the hypothalamus, pituitary, ovaries and adrenal glands.
However, currently is no consensus about what is the root cause of these disorders. Morphological changes in the ovaries may also be caused by local factors - a violation of ovarian function due to a primary defect of the enzyme system, inflammatory diseases, menopause. This can lead to a breach of folliculogenesis or increased production of androgens, which in turn can influence the regulatory mechanisms of the entire reproductive system.
The central genesis of polycystosis is evidenced by the presence hypermelatonine-mia - increasing production of melatonin by pineal gland of the brain (epiphysis). In general features of the hormonal status in polycystosis are reduced levels of estrogen and increased androgen levels, as well as increased excretion of prolactin, melatonin and serotonin due to disruption of the hypothalamic-pituitary system.
The central theory of polycystosis is also confirmed by tendency to reduce the secretion of a number of thyroid hormones, which means that when PCO, thyroid function also is broken. Often the thyroid dysfunction can themselves initiate the development of polycystosis.
Possible causes for the pathogenesis of PCO may be associated with genetic, perinatal, psychogenic and endocrine factors.
Hereditary factors
Scientists admit the possibility of a primary polycystosis caused by genetic factors, but clearly the type of inheritance of polycystic ovaries is not defined, as clinical manifestations of the PCO are diverse, and there are about 40 different genes that can lead to increased production of androgens.
Nevertheless, available data suggest an increased tendency to polycystosis for the presence of complications in the pedigrees, such as:
- malignant tumors and ovarian tumors;
- uterine fibroids;
- high frequency of gestosis in pregnancy;
- diabetes mellitus type 2;
- obesity;
- hirsutism;
- menstrual dysfunction.
In addition, there is a correlation with the age of the parents, because with increasing age of the parents, the likelihood of the mutagenic effect of various external factors on the fetus also increases.
Insulin resistance
Studies in recent years have provided new information on the pathophysiology and pathogenesis of polycystic ovaries. Primarily, this relates to insulin resistance (impaired glucose tolerance) of the organism of patients.
According to the study, polycystosis is associated with increased production of insulin by pancreas. Increased production of insulin in some way associated with increased production of androgens (male sex hormones). This is what causes the imbalance of estrogen and androgen in the body, resulting in polycystic ovarian disease.
These studies have allowed formulating a possible pathogenetic version of polycystosis for women with obesity associated with hyperinsulinemia and insulin resistance, which creates a vicious metabolic circle, leading to violations of the cycle, anovulation, infertility, hirsutism.
In PCO syndrome, 40-60% of women suffer from insulin resistance, which is often accompanied by obesity. With obesity, metabolism of sex hormones is disturbed, because adipose tissue is not only able to accumulate steroids but by itself may produce hormones (extraglandulyar synthesis). Adipose tissue contains 7 times more testosterone, progesterone, and androstenediol than blood plasma, and 2 times more estradiol and estrone.
Weight loss causes a decrease levels of testosterone and androstenediol in blood plasma, thus there is the possibility of pregnancy. Therefore, in the presence of obesity, weight loss should be the first step in treating patients with PCOS.
Insulin resistance, in particular, diabetes mellitus type 2, is observed with polycystosis also in the absence of obesity. PCO, in itself, is also an important risk factor for insulin dependent diabetes mellitus. Scientists believe that diabetes in pre-menopausal women in 10% of cases associated with polycystosis.
Consequently, the role of insulin or insulin-like factors in the pathogenesis of polycystosis can be quite important. At the same time, you may suffer insulin resistance long enough, until it finally lead to the disease or can be detected by doctors.
The role of infections
Doctors do not exclude also the role of infection in the development of polycystosis. A characteristic is the significant frequency of chronic nasal diseases (64.9%) and childhood infections in history of patients with PCO, especially in the central genesis. Cause of PCO development can serve tonsilitis, as the tonsils are closely related to the ovaries, as well as SARS.
It was also shown a role in the PCO pathogenesis of unfavorable factors of production (nicotine, benzene, heavy metals poisoning), long-term use of oral contraceptives and other.
Diagnosis and determination of the PCO causes are complicated by the fact that in various forms of polycystosis, different pathogenetic mechanisms can act. In addition, the practice does not meet one isolated dysfunction of the endocrine glands, without involvement in the pathological process of conjugate functions of other glands.
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