Mechanisms of the development of pain in chronic venous diseases (CVD), including pelvic congestion syndrome (PCS), are studied incompletely. The existing hypotheses of the occurrence of venous pelvic pain (VVP) do not allow to answer the question why some patients have no pain syndrome while others have very pronounced pain despite the same morphofunctional changes in the pelvic veins? The investigators are planning to carry out a study aimed at studying the content of calcitonin gene-related peptide (CGRP) and substance P (SP) in the serum of patients with pelvic veins and pelvic pain, and to study the relationship between the values of CGRP and SP in these patients.

The first phase of the study includes a set of 3 patient groups: the first is patients with pelvic vein dilation and blood reflux through them in combination with venous pelvic pain; the second is patients with pelvic vein dilatation without venous pelvic pain. The third, control group will include healthy female volunteers without pelvic veins and any chronic pain syndromes.

At the second stage of the study, a study will be made of the levels of calcitonin gene-related peptide (CGRP) and the substance P (SP) in the serum using an ELISA method. In addition, after studying the content of the CGRP and SP in the serum of volunteers, the investigators expect to obtain the reference values of these neuropeptides. In this phase of the study, a statistical analysis of the data obtained will be carried out, a correlation analysis between venous pelvic pain and the level of the CGRP and CP.

The data for each patient will be entered into a specially designed patient questionnaire. It will include clinical and ultrasound data, results of ELISA.

Inclusion Criteria:

• The reproductive age of the woman
• Blood reflux in the parametric, uterine, gonadal veins
• The absence of any concomitant pathology, accompanied by chronic pelvic pain

Exclusion Criteria:

• The absence of blood reflux in in the parametric, uterine, gonadal veins
• The presence of diseases, the clinical course of which suggests the presence of chronic pelvic pain and other varieties of chronic pain, including migraine
• Pregnancy

Women aged 18-45 years