The effect of medroxyprogesterone acetate and heparin in the prevention of postsurgical adhesion formation in the rat uterine model.

OBJECTIVE: To evaluate the effects of depot medroxyprogesterone acetate and heparin in preventing postsurgical adhesion formation in the rat model.

METHODS: A hundred and five female Wistar rats were divided into 7 groups. Groups 1 and 2 were injected with intramuscular 15 mg medroxyprogesterone acetate 3 weeks before surgery and at the end of laparotomy. Groups 3 and 4 were given 15 mg medroxyprogesterone acetate by intramuscular injection, 3 weeks before surgery. An equal volume of intramuscular sterile saline was injected to control groups, 3 weeks before and at the end of surgery. Before abdominal closure, 2 ml of Ringer's lactate was instilled into the peritoneal cavity of all rats, except group 7. Groups 1, 4, and 5 were given 2 ml of intraperitoneal Ringer's lactate containing 500 U heparin/ml. A standardized surgical injury was performed in all rats. Two weeks after surgery, the adhesions were scored on a scale of 0 to 3 according to their thickness-tenacity and vascularity. Kruskall-Wallis and Mann-Whitney U statistical test were used.

RESULTS: The preoperative and postoperative administration of medroxyprogesterone acetate resulted in the least number of and the least severe adhesions, when compared with single dose medroxyprogesterone acetate treated rats and controls (p < 0.05). However, the combination of medroxyprogesterone acetate and intraperitoneal heparin did not enhance the adhesion reducing capacity of medroxyprogesterone acetate.

CONCLUSIONS: Concurrent preoperative and postoperative administration of medroxyprogesterone acetate results in the most significant reduction of postsurgical adhesions. The combination treatment of medroxyprogesterone acetate and heparin does not show any additional effect in the reduction of adhesion formation, when compared with medroxyprogesterone acetate treatment alone.