title: Second trimester placental location as a predictor of an adverse pregnancy outcome.
abstract: OBJECTIVE
  To determine if the second trimester placental location is associated with perinatal outcomes.
  
  
  METHODS
  Observational study of placental location and the subsequent risk of an adverse pregnancy outcome. Placental location was divided into three categories, low, high lateral and high fundal.
  
  
  RESULTS
  There were 3336 pregnancies analyzed in this study. Low implantation sites had a greater risk of preterm labor (odds ratio (OR) 1.70, 95% confidence interval (CI) 1.38 to 2.90, P<0.001), preterm delivery (OR 1.86, 95% CI 1.36 to 2.54, P<0.001), fewer fetuses with macrosomia (OR 0.56, 95% CI 0.38 to 0.83, P=0.010) and reduced risk of postpartum hemorrhage (OR 0.56, 95% CI 0.46 to 0.95, P=0.026). High lateral implantations had a greater risk of low 1-min (OR 1.80, 95% CI 1.11 to 2.93, P=0.017) and 5-min (OR 3.49, 95% CI 1.46 to 8.36, P=0.005) Apgar scores.
  
  
  CONCLUSIONS
  Low placental implantation was associated with an increased risk of preterm labor, preterm delivery and a reduced risk of postpartum hemorrhage, and of a macrosomic fetus. High lateral implantation was associated with low Apgar scores.
authors.affiliation: Department of Obstetrics and Gynecology, University of Western Australia, Perth, Australia.
authors.forename: E F
authors.initials: EF
authors.lastname: Magann
authors.forename: D A
authors.initials: DA
authors.lastname: Doherty
authors.forename: K
authors.initials: K
authors.lastname: Turner
authors.forename: G S
authors.initials: GS
authors.lastname: Lanneau
authors.forename: J C
authors.initials: JC
authors.lastname: Morrison
authors.forename: J P
authors.initials: JP
authors.lastname: Newnham
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008875:Middle Aged; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000473:pathology; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D018566:Pregnancy, High-Risk; D012307:Risk Factors