[Material of uterine cavity through retrograde flow into cul-de-sac in suction abortion].

The configuration of uterine cavity and appearance of dark area of fluid were monitored by ultrasound before and after suction abortion in 72 cases during first trimester of pregnancy. Culdocentesis was performed in 10 cases and decidual cells were detected in 18.9%. The results further substantiate the theory of retrograde menstrual flow in the pathogenesis of endometriosis.