The aim of the study was to evaluate the relationship between the shapes of the pelvic cavity, its morphometric characteristics and the distribution of body composition in women in normal conditions and in case of pelvic organs prolapse. Material and methods. The structural features of the female small pelvis were studied on 92 anatomical preparations, and an experimental determination of the value of intra-abdominal pressure on the perineal area was carried out. In the clinical part of the work, 120 women with and without pelvic organ prolapse (n=60) were examined using multislice spiral computed tomography, anthropometry and bioimpedancemetry. Static processing of the obtained data was carried out using the programs “Statistica 10 for Windows”, “Microsoft Excel”. Results. Original indices of the pelvis are proposed, according to which the cylindrical and pelvic cavity forms, which are not previously described, narrowing downwards and cylindrical and downwardly extending. It has been found that the downwardly expanding and cylindrical forms of the pelvic cavity are most often found in women suffering from pelvic organ prolapse. It has been established that the areas of the urogenital and anal areas of the perineum are statistically less with a pelvic shape narrowing downwards than with an expanding one. The value of the sagittal angle of the perineum, as well as the inclination angle of the pelvis in the distribution of intra-abdominal pressure on the tissue of the perineum is shown. At the same time, the inclination angle of the pelvis with prolapse of the pelvic organs is significantly less than that of practically healthy individuals who do not suffer from the disease being studied. A clear correlation between the gynecomorphic body type, the downwardly extending pelvic shape and the development of prolapse is traced. It is shown that the total fat content and visceral fat levels are significantly higher in women suffering from pelvic organ prolapse than in the control group. It is noted that with prolapse of the pelvic organs, the total content of water and fat is about the same, while in practically healthy women the water component significantly predominates over fat. Conclusion. The anatomical prerequisites for pelvic organ prolapse in women are: the downwardly extending shape of the pelvic cavity, an increase in the sagittal angle of the perineum, a decrease in the inclination angle of the pelvis, a gynecomorphic body type and changes in body composition (increase in body mass index, total fat, visceral fat, decrease in total muscle mass).