The pathologic spectrum of uterotubal junction obstruction.

Excised tubal segments from 42 women with uterotubal junction obstruction were studied histologically to evaluate the pathologic spectrum of disease and correlate this with clinical data. The most frequent lesion encountered was obliterative fibrosis (38.1%), confirmed by connective tissue stains, which was not associated with cornual nodularity. Other pathologic entities included salpingitis isthmica nodosa (23.8%), intramucosal endometriosis (14.3%), and chronic tubal inflammation (21.4%). Intramucosal endometriosis was distinguishable from salpingitis isthmica nodosa by virtue of its unique stroma confirmed by connective tissue staining. Women with previous pregnancies were included in all the groups. In all instances, the obstruction was present in the transmural portion of the tube and extended a variable distance into the isthmic segment. These observations on uterotubal junction obstruction demonstrate that: 1) There are multiple distinct histologic patterns, 2) Intraabdominal findings do not predict the histology of the uterotubal junction pathology, 3) Any histologic pattern can be associated with a previous intrauterine or ectopic pregnancy, and 4) The obstruction begins within the transmural portion of the oviduct, extends a variable distance into the isthmic segment, but does not obstruct the ampullary segment. These data suggest that the initiating process originates within the uterus and that fibrosis may represent a nonspecific response to chronic injury of the transmural and isthmic segments of the oviduct.