Problems involving the Passage

Generally, problems with the passage involve restrictions in the size of the hole through the bony part of the pelvis. Although the muscles and ligaments inside the pelvis may present some obstacle, this “soft tissue” (as opposed to bone) will almost always yield to the powers of the uterus.

Very few women actually have a pelvis which is too small to accomodate the average fetus. Often, if a woman has been told she has a small pelvis based on a history of a problem in labor, it is the size/position of the passenger or the force of the powers that is actually the problem. There are, however, a very small percentage of women who have a truly small pelvis or a deformed pelvis due to birth defects, pelvic fractures, or developmental problems. One of the developmental problems, now very uncommon in developed countries, is pelvic deformity due to vitamin deficiencies during childhood……this problem is almost unheard of in countries where adequate nutrition is available. Women with scoliosis, or curvature of the spine, which is relatively common in developed countries, generally do not have a deformed pelvis.