Once a woman goes into labor, it usually progresses in a steady fashion. The pelvic exam can determine the head of the fetus in relationship to the inside of the bones in the birth canal, the pelvis. There is a bony landmark in the pelvis which will be used as the guide in centimeters, as to whether not the fetal head it is minus or plus centimeters as a guide to gauge the progression of the labor. If this woman is a primigravida, that is pregnant for the first time, now and having a vaginal delivery, this is called an “untried pelvis.” And if she has a narrow pelvis, the android shape, more male-like, as opposed to the gynecoid shape of the fuller pelvis, then this is a red flag that there may be a problem with the head of the fetus passing through the birth canal.
If there is no progression of labor down the birth canal, centimeter by centimeter, then this is a problem that may require a cesarean section rather quickly. The fetal heart monitor under these circumstances is really not the better way to determine if they will be a problem. If the umbilical cord is compressed, then the oxygenated blood supply from the uterus to the fetus would be impaired and the fetal heart rate would drop dramatically. That requires it immediately Cesarean section. But in this case of the failure of progression of labor, the umbilical cord is not compressed, but the head is repetitively forced against the inside of the solid bone pelvis. Unlike football players wearing a helmet, this fetal skull has no helmet, and its head is forced under great compression pressure, every few minutes, as opposed to an occasional football concussion. This repetitive concussion will cause brain damage. The failure to observe an obstructed delivery is a departure from the accepted standard of care.