title: Ultrasonic detection of an abnormal mass in a fetus later shown to have trisomy 18.
mesh_terms: D000328:Adult; D002902:Chromosomes, Human, 16-18; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis*; D006801:Humans; D008297:Male; D011247:Pregnancy; D014314:Trisomy; D014463:Ultrasonography; D014521:Urethra / Q000002:abnormalities*; D001743:Urinary Bladder / Q000196:embryology