Salpingitis isthmica nodosa: a high-risk factor for tubal pregnancy.

A prospective and retrospective study was undertaken to analyze pathologic lesions in fallopian tubes of 200 consecutive tubal pregnancies. In a retrospective analysis of 100 cases of tubal pregnancy, seven cases were reported to contain salpingitis isthmica nodosa. After review, 27 cases were found to have this lesion. The prospective study employed 100 consecutive tubal pregnancy specimens thoroughly sectioned for microscopic examination. Salpingitis isthmica nodosa was observed in 57 of these 100 cases. In a control series of 100 fallopian tubes obtained from autopsy and surgical specimens, five tubes showed salpingitis isthmica nodosa. These observations indicate a significant association between tubal pregnancy and salpingitis isthmica nodosa.