title: Biparietal diameter/femur length ratio as predictor of trisomy 21.
authors: J N
authors: JN
authors: Kopelman
authors: K
authors: K
authors: Miyazawa
mesh_terms: D000328:Adult; D002508:Cephalometry; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D005269:Femur / Q000196:embryology*; D005315:Fetal Diseases / Q000175:diagnosis*; D006801:Humans; D009333:Neck; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods; D012867:Skin / Q000196:embryology; D014463:Ultrasonography