BACKGROUND Intra-abdominal complications from transabdominal properitoneal (TAP) laparoscopic herniorrhaphy that would not be expected to occur in an open herniorrhaphy are possible. In a previous study, we reported the incidence of significant intra-abdominal adhesions from TAP herniorrhaphies using polypropylene in pigs. METHODS To compare this with an open herniorrhaphy technique, we performed open herniorrhaphies on 31 pigs. Additional animals underwent TAP herniorrhaphy with PTFE. Data were collected on operative and trocar-site adhesions. Graft incorporation was recorded. RESULTS No intra-abdominal adhesions were found in the 31 animals undergoing open herniorrhaphy. Fifteen adhesions were found in the 31 pigs that underwent TAP herniorrhaphy. These adhesions were graded and there were a total of nine significant adhesions with the TAP procedure. A total of 124 trocar sites resulted in two adhesions. Laparoscopically placed polypropylene was better incorporated than PTFE. The laparoscopically placed PTFE grafts commonly were poorly incorporated. CONCLUSIONS We conclude that there is a risk of intraabdominal adhesions to either the operative site or the trocar sites in TAP herniorrhaphy that is not present in open techniques. One should, therefore, be circumspect in the choice of TAP herniorrhaphy as a primary repair.