2D Transvaginal image of an interstitial ectopic pregnancy. The empty uterine cavity, the myometrial layer of less than 5 mm surrounding the GS, a chorionic sac separated and laterally located >1 cm from the sideward portion of the uterine cavity, the visualization of the interstitial line between the GS and the lateral edge of the endometrial cavity and the myometrial mantle around the ectopic GS.