Infringement of an ovulation: the reasons, signs, diagnostics, treatment

The violation of ovulation is pathological, irregular or absent ovulation. In this case, menstruation is often irregular or absent. The diagnosis is based on anamnesis or can be confirmed by measurement of hormonal levels or pelvic ultrasonography. Treatment of ovulation disorders is performed by induction of ovulation with clomiphene or other drugs.

Chronic ovulation in women in the premenopausal period is in most cases associated with polycystic ovary syndrome (PCOS), but also has many other causes, such as hyperprolactinaemia and hypothalamic dysfunction (hypothalamic amenorrhea).

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Symptoms of ovulation disorder

It is possible to suspect the violation of ovulation in cases where menstruation is irregular or absent, there is no previous swelling of the mammary glands, there is no abdominal enlargement or irritability.

The daily morning basal temperature measurement helps determine the timing of ovulation. However, this method is inaccurate and there may be errors within 2 days. More accurate methods include the use of home tests to detect an increase in the excretion of LH in the urine within 24-36 h before ovulation, pelvic ultrasound in order to observe the growth of the diameter of the ovarian follicle and its rupture. It is also helpful to determine progesterone levels in serum 3 ng / ml (9.75 nmol / L) or to determine elevated levels of the metabolite of pregnanediol glucuronide in urine (measured as possible 1 week before the start of the next monthly period); these indicators indicate the onset of ovulation.

With irregular ovulation, pituitary, hypothalamic, or ovarian disorders (eg, PCOS) are detected.

Treatment of ovulation disorder

Ovulation can be induced with drugs. Usually, in the presence of chronic anovulation as a result of hyperprolactinaemia, the initial treatment is performed with the appointment of an antiestrogen, clomiphene citrate. In the absence of monthly uterine bleeding is caused by the appointment of medroxyprogesterone acetate 5-10 mg orally once a day for 5-10 days. Assign clomiphene to 50 mg from the fifth day of the menstrual cycle for 5 days. Ovulation is usually noted on the 5th-10th day (usually the 7th day) after the last day of taking clomiphene; if ovulation occurs, the next menstruation is noted 35 days after the previous menstrual bleeding. The daily dose of clomiphene citrate can be increased by 50 mg every 2 cycles with a maximum dosage of 200 mg / dose to induce ovulation. Treatment can be continued as needed for 4 ovulatory cycles.

Adverse effects of clomiphene are vasomotor flushes (10%), bloating (6%), breast tenderness (2%), nausea (3%), visual symptoms (1-2%), headaches (1-2%). Multiple pregnancy (twins) and ovarian hyperstimulation syndrome occur in 5% of cases. Most often develop ovarian cysts. The preliminary assumption that there is a link between the appointment of clomiphene for more than 12 cycles and ovarian cancer has not been confirmed.

For patients with PCOS, most of whom have insulin resistance, prescribe drugs that increase insulin sensitivity before ovulation induction. These include metformin 750-1000 mg orally once a day (or 500-750 mg orally 2 times a day), less often prescribed thiazolidinedione (for example, rosiglitazone, pioglitazone). If insulin sensitivity is ineffective, clomiphene may be added.

Patients with ovulatory dysfunction who do not respond to clomiphene can be prescribed drugs of human gonadotropin (for example, containing purified or recombinant FSH and variable amounts of LH). These drugs are prescribed intramuscularly or subcutaneously; they usually contain 75 IU of FSH in combination with or without active LH. These drugs are usually prescribed 1 time per day, from the 3-5th day after induced or spontaneous bleeding; ideally they stimulate the maturation of 1-3 follicles, determined by ultrasonography within 7-14 days. Ovulation is also induced by HCG 5000-10 000 ME intramuscularly after maturation of the follicle; the criteria for induction of ovulation may vary, but a more typical criterion is an increase in at least one follicle to a diameter greater than 16 mm. However, induction of ovulation in patients with a high risk of multiple pregnancies or with ovarian hyperstimulation syndrome is not performed. Risk factors include the presence of more than 3 follicles with a diameter greater than 16 mm and preovulatory levels of estradiol in the serum of more than 1500 pg / ml (possibly more than 1000 pg / ml in women with several small ovarian follicles).

After gonadotropin therapy, 10-30% of successful pregnancies are multiparticulates. Ovarian hyperstimulation syndrome occurs in 10-20% of patients; the ovaries significantly increase in size with the presence of fluid in the peritoneal cavity, causing potentially life-threatening ascites and hypovolemia.

Major disorders require treatment (eg, hyperprolactinaemia). In the presence of hypothalamic amenorrhea for the induction of ovulation, gonadorelin acetate (synthetic GnRH) is prescribed as an intravenous infusion. Assignable bolus doses of 2.5-5.0 μg (heart rate) regularly every 60-90 minutes are the most effective. Gonadorelin acetate rarely causes multiple pregnancies.