Plasma endorphin-like immunoreactivity in pelvic and abdominal pain.

This study was undertaken to determine the association, if any, of plasma endorphins with pelvic pain in a defined population. The study group was comprised of 37 patients who presented to the emergency room at Wishard Memorial Hospital for evaluation of gynecologic complaints. These subjects were divided into 3 groups depending on the degree of pelvic pain assessed both by the subject and the examining physician. Group I (control) consisted of those subjects who were pain-free (9 subjects). Group II contained those whose pelvic pain was not felt to require hospital admission (18 subjects). Group III subjects represented those with pelvic pain whose diagnosis warranted hospitalization (10 subjects). Plasma endorphin levels were determined on each subject before and after pelvic examination using standard radioimmunoassay techniques. Data analysis was accomplished by analysis of variance methods. The timing of the pelvic examination made no difference on the plasma endorphin levels. Levels between groups were statistically similar, though differences between both group I and group II, and that of group III levels approached significance.