title: Ultrasound of the empty gestation sac in threatened abortion.
abstract: The major concern when an empty gestation sac is encountered during threatened abortion is whether or not the pregnancy is viable. Viable pregnancies are managed expectantly, whereas non-viable pregnancies are treated by evacuation of the uterus. Early evacuation of the non-viable pregnancy spares the patient considerable anxiety and discomfort. This study shows that a single ultrasound examination is useful in differentiating viable from non-viable empty gestation sacs. The size of the empty gestation sac was found to be the most useful criterion for determining non-viability. Empty gestation sacs with sizes greater than 26 mm were non-viable, a specificity of 100%, accounting for 43% (42 out of 102) of patients in our series. Other ultrasound criteria found to be useful were shape, position, wall and decidual reaction. The positive predictive value for a successful outcome to a pregnancy was low, being only 41% (9 out of 22).
mesh_terms: D000033:Abortion, Threatened / Q000175:diagnosis*; D005321:Extraembryonic Membranes / Q000033:anatomy & histology*; D005260:Female; D005328:Fetal Viability; D006801:Humans; D011247:Pregnancy; D014463:Ultrasonography