CHARACTERISTICS OF THE LOWER UTERINE SEGMENT HEMODYNAMICS DEPENDING ON THE PRESENCE OF LABOR

Aim. Using laser Doppler flowmetry (LDF) and intraoperative ultrasound diagnostics, to study the characteristics of blood flow and myometrial thickness in the lower uterine segment in women at full-term pregnancy, depending on the presence or absence of labor.

Material and methods. The study included 55 women in full-term pregnancy who gave birth for the first time by cesarean section, of which 33 (60%) women before the onset of labor and 22 (40%) after the onset of regular labor. During the operation, after surgical access to the abdominal cavity, all patients were assessed for the hemodynamics of the lower uterine segment using laser Doppler flowmetry, as well as for the thickness of the myometrium in this segment using intraoperative ultrasound diagnostics.

Results. It was established that in the group of women who underwent a cesarean section in the presence of labor, hemodynamic indicators of the lower uterine segment were registered: perfusion of the microvasculature (PM, perfusion unit (pf.u.) – 5.04 [1.26;5.8 ], standard deviation (RMS, pf.ed) – 3.6 [2.6;3.71], coefficient of variation (Kv, %) – 16.0 [12.4;16.2]. In the group of women who had abdominal delivery at the similar time of pregnancy, but in the absence of labor contractions, hemodynamic parameters were: PM – 6.6 [5.02;7.02], SD – 3.41 [3.0;3.7], Kv, % – 16.0 [12.6;16.5]. Further statistical analysis of the obtained data revealed that in the group of women who underwent cesarean section in the presence of labor, the hemodynamic parameters of the lower uterine segment, assessed using laser Doppler flowmetry, and the thickness of the myometrium in it was significantly lower than in the group of women who were delivered abdominally before the onset of labor.

Conclusion. Patients who have had a cesarean section after the onset of labor have a decrease in microcirculation and myometrial thickness in the lower segment of the uterus, which must be taken into account when predicting the course of myometrial reparative processes, primarily angiogenesis in this area and the characteristics of scar tissue formation.

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