The most common endocrine disorder in women of childbearing age, polycystic ovary syndrome, or PCOS, is not always easy to diagnose. His involvement in infertility is frequent but not systematic.
What is polylystic ovary syndrome?
Polycystic ovary syndrome is an endocrine pathology. It is also known as Stein-Leventhal syndrome after the two doctors who first described it in 1935.
Its name refers to one of the aspects of this syndrome visible on ultrasound, namely the accumulation around the ovaries of multiple small cysts. These cysts are actually follicles that refuse to grow during the last stage of the follicular phase. This aspect, however, is only one facet of PCOS, a syndrome that can manifest itself differently among women in more or less complete forms, with multiple repercussions on women’s health.
In its complete form, PCOS causes an absence of ovulation and therefore an impossibility to become pregnant. 50% of women with PCOS have primary infertility, and 25% secondary infertility. PCOS is thus responsible for more than 70% of infertility by anovulation. Infertility is therefore frequent, but not systematic.
Causes of Polycystic ovary syndrome
The physiopathological mechanisms underlying PCOS are not yet well known and they certainly cannot be explained by a single cause, but by a succession of causes that act in a vicious circle. Basically, there is hyperandrogenism, that is, excessive secretion of androgens, and insulin resistance. Both are likely to be of genetic origin.
PCOS is the most common endocrine pathology in women of childbearing age, with 5% to 10% of women affected.
Evolution and possible complications
PCOS affects the ovaries but since it is an endocrine disease, it has an impact on the entire hormonal balance and can lead to various metabolic, cardiovascular, reproductive and general complications. We are talking about systemic affection. Possible complications include:
- In pregnancy, an increased risk of miscarriage, premature labor, gestational diabetes, and pre-eclampsia. This risk is all the more increased in case of overweight;
- glucose intolerance and type 2 diabetes;
- lipid abnormalities (hypertriglyceridaemia, hypercholesterolemia);
- high blood pressure
- depression ;
- sleep apnea syndrome;
- cardiovascular diseases (macroangiopathy, thrombophilia);
- Some female cancers (endometrium, breast, ovarian according to some studies, but other risk factors such as obesity is to be taken into account).
Symptoms of Polycystic Ovary Syndrome
The PCOS can manifest it by different clinical signs, with different tables and degrees according to the women:
- irregular (spaniomenorrhea), infrequent (oligomenorrhea) or absent (amenorrhea)
- excessive bleeding during menstruation (menorrhagia)
- an increase in the volume of the ovaries with the formation of many small cysts inside;
- Difficulties to conceive.
Skin disorders, consequences of androgyny:
- Hirsutism (hair on normally glabrous areas in women: face, neck …). This sign is found in 70% of women with PCOS
- alopecia (hair loss)
Or signs of an insulin-resistance:
- a Nigerian acanthosis (browning and thickening of the skin in the neck area, groin, armpits and skin folds)
- weight gain or obesity;
- an increase in the blood sugar level;
The hereditary factor is to date the only risk factor suspected.
Diagnostic of Polycystic ovary syndrome
The clinical heterogeneity of PCOS sometimes makes diagnosis difficult.
In 2003, the first diagnostic criteria for PCOS were established. These are the Rotterdam criteria. In 2013, the American Society of Endocrinology established new recommendations for the diagnosis of PCOS, adopted in 2014 by the European Society of Endocrinology. Today, the diagnosis of PCOS is made in the presence of at least 2 of the Rotterdam criteria, namely:
- clinical hyperandrogenism (hirsutism, acne, androgenic alopecia) or biological
- Oligo-anovulation (irregular or absent ovulation). According to the Rotterdam criteria, cycles shorter than 21 days or greater than 35 days are considered anovulatory;
- on the endovaginal ultrasound, the presence of at least one ovary with more than 12 follicles of 2 to 9 mm and diameter and / or an ovarian volume greater than 10 ml without presence of cyst or dominant follicle.
To establish this diagnosis, besides the interrogation on the medical and gynecological antecedents, various examinations are carried out:
- cycle analysis;
- a clinical examination;
- an endovaginal ultrasound of the ovaries (in 2D or 3D);
- Hormonal assays (testosterone, delta 4 androstenedione, LH, FSH, oestradiol, 17 hydroxyprogesterone, a glycemic balance and HCG).
Before diagnosing PCOS, it is important to rule out other conditions: congenital adrenal hyperplasia, hyperprolactinemia, thyroid disorder.
Treatment of Polycystic ovary syndrome
There is no cure for PCOS. Management is therefore based on the treatment of manifestations of the syndrome and the prevention of complications, especially cardiovascular:
- Against hyperandrogenism and the various manifestations that result from it (disorders of the rules, acne, hirsutism), a contraception of the type estrogen-progestative is the treatment of first intention (in case of no desire of pregnancy). Progesterone inhibits the secretion of LH (luteinizing hormone) and by this biai production of ovarian androgens, while estrogen will increase sex hormone binding globulin (SHGB), a sex hormone binding protein, with the effect of decrease in bioavailable androgen levels;
- In overweight or obese women, weight loss is recommended to limit metabolic complications. This loss of weight may also be sufficient to restore ovulation in some patients;
- Against infertility, clomiphene citrate is the first-line treatment for PCOS-induced ovulation disorders. This ovulation inducer is an anti-estrogen: it blocks the estrogen receptors in the hypothalamus, which leads to an increase in GnRH and FSH levels and facilitates the maturation of the follicles. The induction of ovulation by clomiphene citrate makes it possible to obtain pregnancy in 35 to 40% of patients. Other treatments may be considered in case of failure of hormonal stimulation (usually after 6 test cycles):
- Other hormonal stimulation treatments: a combination of metformin-clomiphene citrate, gonadotropin, or aromatase inhibitors, such as Letrozole. The latter seems promising ;
- ovarian drilling: this surgical technique involves performing a “multiperforation” of the ovary under laparoscopy in order to restore its proper functioning;
- In vitro fertilization sometimes preceded by in vitro maturation of oocytes (MIV) (oocytes are collected before ovulation, at a late stage of follicular maturation, and finish their maturation in vitro).
- Against insulin resistance, different treatments are under study. Treatment with metformin is recommended in patients with diabetes or pre-diabetes, after failure of dietary and lifestyle measures.
It is not possible to prevent PCOS, however diet and lifestyle measures to combat overweight are essential to prevent complications.