Ultrasonographic differentiation of cervical abortion from cervical pregnancy.

Cervical abortion is a spontaneous abortion of a normal intrauterine pregnancy into the cervical canal where the abortus is retained by a closed external os, causing distention of the cervical canal. This entity closely simulates ectopic cervical pregnancy clinically. The ultrasonic findings in four patients with cervical abortion are described and these could alert the physician to the possibility of this condition.