The histopathology of the developing tubal ectopic pregnancy.

Examination of histopathologic sections taken of tubal ectopic pregnancies and gross dissections of these specimens suggest that, in the majority of cases, the growth of the developing trophoblast takes place in a largely extratubal site and that the common clinical impression that the mass associated with the tubal ectopic pregnancy is a dilated fallopian tube is largely erroneous.