title: Placental Insufficiency in Fetuses That Slow in Growth but Are Born Appropriate for Gestational Age: A Prospective Longitudinal Study.
abstract: OBJECTIVE
  To determine whether fetuses that slow in growth but are then born appropriate for gestational age (AGA, birthweight >10th centile) demonstrate ultrasound and clinical evidence of placental insufficiency.
  
  
  METHODS
  Prospective longitudinal study of 48 pregnancies reaching term and a birthweight >10th centile. We estimated fetal weight by ultrasound at 28 and 36 weeks, and recorded birthweight to determine the relative change in customised weight across two timepoints: 28-36 weeks and 28 weeks-birth. The relative change in weight centiles were correlated with fetoplacental Doppler findings performed at 36 weeks. We also examined whether a decline in growth trajectory in fetuses born AGA was associated with operative deliveries performed for suspected intrapartum compromise.
  
  
  RESULTS
  The middle cerebral artery pulsatility index (MCA-PI) showed a linear association with fetal growth trajectory. Lower MCA-PI readings (reflecting greater diversion of blood supply to the brain) were significantly associated with a decline in fetal growth, both between 28-36 weeks (p = 0.02), and 28 weeks-birth (p = 0.0002). The MCA-PI at 36 weeks was significantly higher among those with a relative weight centile fall <20%, compared to those with a moderate centile fall of 20-30% (mean MCA-PI 1.94 vs 1.61; p<0.05), or severe centile fall of >30% (mean MCA-PI 1.94 vs 1.56; p<0.01). Of 43 who labored, operative delivery for suspected intrapartum fetal compromise was required in 12 cases; 9/18 (50%) cases where growth slowed, and 3/25 (12%) where growth trajectory was maintained (p = 0.01).
  
  
  CONCLUSIONS
  Slowing in growth across the third trimester among fetuses subsequently born AGA was associated with ultrasound and clinical features of placental insufficiency. Such fetuses may represent an under-recognised cohort at increased risk of stillbirth.
authors.affiliation: Department of Perinatal Medicine, Mercy Hospital for Women, Melbourne, Australia.|La Trobe University, Mercy Hospital for Women, Melbourne, Australia.
authors.forename: Nadia
authors.initials: N
authors.lastname: Bardien
authors.affiliation: Department of Perinatal Medicine, Mercy Hospital for Women, Melbourne, Australia.|Translational Obstetrics Group, University of Melbourne, Melbourne, Australia.
authors.forename: Clare L
authors.initials: CL
authors.lastname: Whitehead
authors.affiliation: Department of Perinatal Medicine, Mercy Hospital for Women, Melbourne, Australia.|Translational Obstetrics Group, University of Melbourne, Melbourne, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Tong
authors.affiliation: School of Physiotherapy, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Antony
authors.initials: A
authors.lastname: Ugoni
authors.affiliation: La Trobe University, Mercy Hospital for Women, Melbourne, Australia.
authors.forename: Susan
authors.initials: S
authors.lastname: McDonald
authors.affiliation: Department of Perinatal Medicine, Mercy Hospital for Women, Melbourne, Australia.|Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Australia.
authors.forename: Susan P
authors.initials: SP
authors.lastname: Walker
mesh_terms: D000328:Adult; D001724:Birth Weight; D001921:Brain / Q000196:embryology; D002585:Cesarean Section; D036861:Delivery, Obstetric; D047108:Embryonic Development; D005260:Female; D047109:Fetal Development; D005316:Fetal Distress / Q000209:etiology; D005317:Fetal Growth Retardation / Q000209:etiology*; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010927:Placental Insufficiency / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D012306:Risk; D016037:Single-Blind Method; D050497:Stillbirth / Q000453:epidemiology; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries; D055815:Young Adult