Objective: To determine which ovarian sex steroid(s), when removed from an intact organism, reduce(s) postoperative adhesion development.
Design: Randomized, prospective, blinded study.
Setting: University vivarium.
Patient(s): One hundred twenty sexually mature female Sprague-Dawley rats, 226-250 g.
Intervention(s): Day 0, sham ovariectomy or bilateral ovariectomy, accompanied by continuous-release sex steroid replacement of either no steroids (control), 17beta-E(2), natural P (P4), or combined E(2)/P4. Day 7, standardized cecal abrasion; day 14, necropsy with assessment of adhesion presence or absence.
Main outcome measure(s): Adhesion formation.
Result(s): Three rats died because of anesthesia or surgical complications, and 117 rats reached necropsy. The ovary-intact (sham) rats adhesion incidence was 60.9%; ovariectomized control rats, 20.8%; E(2), 28.6%; P4, 33.3%; and combined E(2)/P4, 24.0%. Despite differing sex steroid replacement, two-tailed chi(2) testing with correction for multiple comparisons showed no statistical difference in adhesion incidence among the four ovariectomy groups. A statistically significant lower adhesion incidence was noted between the ovary-intact sham cohort and the collective ovariectomy groups and between the sham and ovariectomized control cohorts.
Conclusion(s): Ovarian presence or absence at the time of surgical wounding, and not the 17beta-E(2) or P milieu, modulates adhesion development. This implicates other ovarian factor(s) in postoperative adhesion development.