What is the reason that pelvis is not wide

Update Date: 2021-06-26 Source: Network

summary

If the pelvic diameter is too short or the shape is abnormal, the pelvic cavity is smaller than the limit of fetal presentation, which hinders the descent of fetal presentation and affects the smooth progress of labor. Narrow pelvis can be one or more short diameter lines, or one plane narrow or multiple planes narrow at the same time. When a diameter line is narrow, we should observe the size of other diameters in the same plane. Let's take a look at the following.

What is the reason that pelvis is not wide

First, it can be judged by pelvic external measurement. For example, if the diameter line of pelvic external measurement is less than or equal to the normal value of 2cm or more, it is a small pelvis, but if the sacral external diameter is less than 18cm, it is a flat pelvis. The diameter between ischial tubercles was less than 8 cm, and the angle of pubic arch was less than 90 ° All of them can be classified as pelvic stenosis.

Second: it can also be judged by pelvic measurement. If there is no abnormality in pelvic lateral measurement, pelvic measurement should be carried out. For example, if the diagonal diameter is less than 11.5cm, the sacral promontory is protruding and the pelvic entrance plane is narrow, which belongs to flat pelvis. The middle pelvic plane stenosis and the pelvic outlet plane stenosis often coexist.

Third, we must pay attention to the treatment of delivery with narrow pelvis. We must make clear the type and degree of narrow pelvis, understand the fetal position, fetal size, cervical dilatation, rupture of membranes or not, and determine the mode of delivery based on the comprehensive judgment of age, parity and previous delivery history.

matters needing attention

Because during childbirth, the pelvis is a constant factor. Narrow pelvis affects the descent and internal rotation of fetal position and fetal presentation in the delivery mechanism, and also affects uterine contraction. The pelvis is an important factor in estimating the difficulty of delivery.