BACKGROUND
Hormonal contraception is the modern and most effective method of preventing an unwanted pregnancy, based on the use of synthetic analogues of female sex hormones. Combined oral contraception is a type of hormonal contraception that involves cyclic oral administration of drugs containing estrogens and progestogens.
OBJECTIVES
To evaluate intermenstrual spotting and angiogenic affects contraception with a combined estrogen-progestogen preparation containing ethinyl estradiol and dienogest.
METHOD
Enzyme immunoassay was used to determine the content of VEGF-A and VEGF P1 in the blood; immunohistochemistry was used to evaluate the expression of VEGF-A in the epithelium of the glands and the density of microvessels — CD31 in the eutopic endometrium; determination of blood biochemical parameters was carried out under standardized results, the determination of blood hemostasiogram parameters was carried out according to the results of studies of procoagulant and platelet units, markers of intravascular coagulation; Dopplerometry of the vessels of the uterus and veins of the lower extremities was carried out, the function of the endothelium was studied. Studies were carried out before contraception, and then after 3, 6 and 9 months against the background of its use.
RESULTS
To using COC containing ethinyl estradiol and dienogest, significant changes in angiogenesis parameters have been established. Statistically significant differences were observed at the systemic and local levels. This is due to the effect of COC on microvessel density in the endometrium and expression of VEGF-A in the epithelium of the endometrial glands by the 9th month of contraception. A decrease in the concentration of VEGF-A in the blood due to an increase in the content of VEGF R1 in patients with intermenstrual spotting indicates the effect of COC on VEGF R1, which can alter the functional activity of the endometrial microvessels, lead to their damage and thereby contribute to the appearance of intermenstrual spotting.
CONCLUSION
Using third-generation COC, intermenstrual spotting is observed, which is characterized by features of the effect on the processes of angiogenesis in women. The established features make it possible to identify risk groups of women with low rates of angiogenesis before starting COC, which will help prevent intermenstrual spotting by contraception and thereby reduce the level of adverse reactions against contraception.
