title: Sonographic appearance of a pathologic retraction ring.
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007744:Obstetric Labor Complications / Q000175:diagnosis*; D011247:Pregnancy; D014463:Ultrasonography; D014590:Uterine Contraction; D014599:Uterus / Q000473:pathology*