Ultrasonic visualization of a dilated cervix during pregnancy.
D000033:Abortion, Threatened / Q000503:physiopathology*; D000328:Adult; D002584:Cervix Uteri / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature / Q000503:physiopathology*; D011247:Pregnancy; D014463:Ultrasonography; D002581:Uterine Cervical Incompetence / Q000175:diagnosis*