title: The fetal frontomaxillary facial angle in normal and trisomy 21 ultrasounds at 11-13(+6) weeks of gestation: findings among the ethnic Chinese compared with Caucasian.
abstract: OBJECTIVE
  The aim of this research was to compare the fetal frontomaxillary facial (FMF) angle between normal and trisomy 21 fetuses at 11(+0) -13(+6)  weeks gestation in a Chinese population.
  
  
  METHODS
  A prospective observational study was performed that included 640 euploid and 45 trisomy 21 singleton pregnancies undergoing first trimester ultrasound screening between 11 and 13(+6)  weeks of gestation. The FMF angle was measured in the midsagittal plane using the standard technique.
  
  
  RESULTS
  The fetal mean FMF angle decreased with the increasing crown-rump length (CRL) from 88.6°at a CRL of 45 mm to 78.5° at a CRL of 84 mm (FMF angle = 100.212 - 0.258 × CRL, R(2)  = 0.222, p < 0.001). The overall mean FMF angle in the euploid population was 82.9° ± 4.1° and in trisomy 21 cases, 92.3° ± 5.2°.
  
  
  CONCLUSIONS
  Fetal FMF angle is affected by gestational age in a Chinese population, although it remains a significant predictor of fetal trisomy 21.
authors: Department of Obstetrics and Gynecology, Taipei City Hospital, Women and Children Campus, Taipei, Taiwan, ROC.
authors: Ching Hua
authors: CH
authors: Hsiao
authors: Wen Liang
authors: WL
authors: Liu
authors: Ran Chou
authors: RC
authors: Chen
authors: Bo Jen
authors: BJ
authors: Cheng
authors: Yin Jiun
authors: YJ
authors: Tseng
authors: Woei Chyn
authors: WC
authors: Chu
mesh_terms: D000328:Adult; D044466:Asian People; D004314:Down Syndrome / Q000000981:diagnostic imaging* / Q000208:ethnology*; D005145:Face / Q000000981:diagnostic imaging* / Q000196:embryology; D005260:Female; D005333:Fetus / Q000033:anatomy & histology; D005865:Gestational Age; D006801:Humans; D008437:Maxilla / Q000000981:diagnostic imaging* / Q000196:embryology; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000208:ethnology; D011262:Pregnancy Trimester, Second / Q000208:ethnology; D016216:Ultrasonography, Prenatal / Q000379:methods*; D044465:White People; D055815:Young Adult