From the International Chiropractic Pediatric Association website:
The Webster technique is a specific chiropractic analysis and diversified adjustment. The goal of the adjustment is to reduce the effects of sacral subluxation/ SI joint dysfunction. In so doing neuro-biomechanical function in the pelvis is improved.
Sacral subluxation may contribute to difficult labor for the mother (i.e., dystocia). Dystocia is caused by inadequate uterine function, pelvic contraction, and baby mal-presentation. The correction of sacral subluxation may have a positive effect on all of these causes of dystocia.
It is proposed that sacral misalignment may contribute to these three primary causes of dystocia via uterine nerve interference, pelvic misalignment and the tightening and torsion of specific pelvic muscles and ligaments. The resulting tense muscles and ligaments and their aberrant effect on the uterus may prevent the baby from comfortably assuming the best possible position for birth.
It is therefore considered prudent that this specific sacral analysis and adjustment be used throughout pregnancy to detect and alleviate sacral imbalance and optimize pelvic neuro-biomechanics in the mother. Because of the particular female adaptations from the increase of hormones, weight gain and postural adaptations, pregnant mothers have a greater chance of sacral subluxation and neuro-biomechanical imbalance than the general population. Additionally, because of the effect the chiropractic adjustment has on all body functions by reducing nerve system stress, pregnant mothers may have significant benefit by having their spines checked regularly throughout pregnancy, optimizing health benefits for both the mother and baby.