In 141 consecutive cases of tubal ectopic pregnancy at Hermann Hospital in Houston, Texas, the histologic appearance of 129 surgically removed fallopian tubes containing ectopic pregnancies was reviewed and compared with an age- and race-matched control population. There was a higher incidence of chronic salpingitis (88 versus 2%) and salpingitis isthmica nodosa (SIN) (43 versus 5%). The ectopic pregnancy patients had a higher incidence of pelvic inflammatory disease, gonorrhea, previous abortions, bitubal ligation, intrauterine device use, and previous abdominal surgery. In our population, chronic salpingitis was the most commonly associated finding. The increase in SIN was associated with postinflammatory changes (89%). We also found that ectopic tubal pregnancies may grow either intratubally or extratubally by villous invasion into the wall and blood vessels; therefore, surgical salvage of the fallopian tube by extracting the products of conception will not always be curative.