The effect of squatting on pelvic dimensions.
Lateral X-ray pelvimetry was performed on 63 women in the sitting and squatting positions on the 5th or 6th post-natal day to assess whether squatting has any effect on pelvic dimensions. Four assessors measured the inlet and outlet pelvic dimensions from 25 cases with good radiographic views in order to minimise observer bias. There was no statistically significant change in pelvic dimensions with squatting. Some possible explanations are discussed.