Effect of patient position on clinical evaluation of pelvic organ prolapse

To compare the severity of pelvic organ prolapse between examinations performed in dorsal lithotomy position and examinations performed upright in a birthing chair using the Pelvic Organ Prolapse Quantification System (POPQ).

One hundred eighty-nine consecutive women were evaluated between April 1997 and September 1998. All women were examined in the dorsal lithotomy position and in a birthing chair at a 45 degrees angle. Degree of pelvic organ prolapse was assessed using the POPQ.

When examined upright, 133 patients (70%) had the same stage of prolapse, whereas 49 (26%) had a higher stage and seven (4%) had a lower stage. Of patients who were stage 0 or I when examined in lithotomy position, 23 (36%) were stage II or greater when examined upright. Similarly, of patients who were stage II in lithotomy, 17 (23%) were stage III or higher when examined upright. There was a statistically significant increase in the degree of prolapse at all the POPQ measurements (P <.05 for each point), except for measurement of total vaginal length. Forty-eight percent of patients had at least one measurement increase by 2 cm or more when examined upright. Logistic regression identified no patient characteristics that were independently associated with a significant increase in stage or POPQ values with change in examination position.

The degree of pelvic organ prolapse assessed with the patient in the lithotomy position correlates well with assessment performed upright; however, overall there is a higher degree of prolapse with upright examination.