First of all, the physician must visually inspect the pregnant woman. The so-called "diamond Michaelis" can tell a lot about the structure of the pelvis. This site is located on the lower back. It must conform to the shape of an inverted square. If the doctor sees that side corners are slightly shifted to each other, it indicates a narrow pelvis, which means that natural childbirth are called into question.
After that, the doctor should go to the measurement of the pelvic bones. For this purpose there is a special measuring device called tazomerom. The patient is asked to lie down on the couch belly up, ends tazomera put on the front upper iliac spine (2). The results recorded. Then, measure the space between distant points of the ridges above mentioned bones, it is located just above the previous place of measurement (1).
Next, put on the ends tazomera trochanter, they are located just below the waist (3).
After that, the doctor must know the smallest size within the pelvis. To do this, the patient is asked to turn to the side, bend the underlying leg at the knee and hip joints. One end tazomera put on the pubic bone, behind the pubic symphysis is located, and the other end - at the sacral region. Is subtracted from the result of 9 cm, so the obstetrician to determine the true size of the conjugates. If it is less than 10, 5, in most cases, physicians prescribe caesarean section.
In order to most accurately determine the size of the pelvis, you can go through x-ray of the pelvis, a survey done only in the last months of pregnancy, because before that period bones kid still not formed.