Many people think that the difficulty of childbirth can be seen from the body shape of pregnant women, but this is not absolutely correct. It is invisible to the naked eye to judge the difficulty of childbirth. The difficulty of delivery is determined by the contractility of pelvis, fetus and uterus.
What are the factors that determine dystocia?
embryo
Postpartum posture, mode, posture, body position, head circumference, chest circumference, number of fetuses and fetal health may all affect the progress of labor and the mode of production.
Uterine contractility
At present, we still don't know the real mechanism of starting childbirth. Under normal circumstances, about 40 weeks of pregnancy may be caused by the stretching of the uterus to a certain extent, the stimulation of the cervical plexus, the production of special hormones by the placenta, the decrease of estrogen and organic lutein in the blood, and physiological or psychological factors.
basin
The pelvis is composed of the innominate bone (surrounded by intestine, ischium and pubic bone), sacrum and coccyx, which is the "birth canal". When evaluating pelvic fertility, the most important measurement is: 1) Obstetric diameter at the entrance. 2) The distance between the ischial spines. 3) The distance between the inferior pubic horn and the two nodules. 4) The posterior sagittal diameter of three planes (entrance, middle and exit). 5) The curvature and length of the sacrum.
The scope of these objective assessments can only be measured by pelvic radiography. However, radiation exposure may increase the chances of children suffering from blood tumors in the future, so it is not widely used. Generally speaking, this kind of examination will only be considered if the progress of labor is slow. Or according to clinical judgment and ultrasound examination, it is necessary to adopt caesarean section to determine whether there is asymmetry between fetal head and pelvis. Because women's pelvis and the plane of each pelvis vary greatly, it is impossible to classify the pelvis rigidly.
What are the factors that determine dystocia?
For practical needs, according to the shape of the pelvic entrance, we can divide the pelvis into:
1) female round or oval.
2) A man's heart is still wedge-shaped.
3) anthropoid ape, that is, long oval shape.
4) Flat, that is, transverse oval, but the front and rear diameter is very short.
Of these four types of pelvis, "female type" and "ape type" are more conducive to childbirth. Both "male" and "flat" are not conducive to vaginal delivery. Of course, the shape of the pelvis is invisible to the naked eye, and the idea that a big ass will have children is just speculation.