Value of third-trimester cerebroplacental ratio and uterine artery Doppler indices as predictors of stillbirth and perinatal loss

Ultrasound Obstet Gynecol. 2016 Jan;47(1):74-80. doi: 10.1002/uog.15729.

Abstract

Objective: Placental insufficiency contributes to the risk of stillbirth. Cerebroplacental ratio (CPR) is an emerging marker of placental insufficiency. The aim of this study was to evaluate the association of third-trimester fetal CPR, uterine artery (UtA) Doppler and estimated fetal weight (EFW) with stillbirth and perinatal death.

Methods: This was a retrospective cohort study including 2812 women with a singleton pregnancy who underwent an ultrasound scan in the third trimester. EFWs were converted into centiles, and Doppler indices (UtA and CPR) were converted into multiples of the median (MoM), adjusting for gestational age. Regression analysis was performed to identify, and adjust for, potential confounders, and receiver-operating characteristics (ROC) curve analysis was used to assess the predictive value.

Results: When adjusting for EFW centile and UtA mean pulsatility index (UtA-PI) MoM, CPR-MoM remained an independent predictor of stillbirth (odds ratio (OR) = 0.003 (95% CI, 0.00-0.11), P = 0.003) and perinatal mortality (OR = 0.001 (95% CI, 0.00-0.03), P < 0.001). UtA-PI ≥ 1.5 MoM was significantly associated with low CPR-MoM, even after adjusting for EFW centile (OR = 5.22 (95% CI, 3.88-7.04), P < 0.001) or small-for-gestational age (SGA; OR = 4.73 (95% CI, 3.49-6.41), P < 0.001). These associations remained significant, even when excluding pregnancies with SGA or including only cases in which Doppler indices were recorded at term (P < 0.01). For prediction of stillbirth, the area under the ROC curve, using a combination of these three parameters, was 0.88 (95% CI, 0.77-0.99) with a sensitivity of 66.7%, specificity of 92.1%, positive likelihood ratio (LR) of 8.46 and negative LR of 0.36.

Conclusions: Third-trimester CPR is an independent predictor of stillbirth and perinatal mortality. The role of UtA Doppler, CPR and EFW in assessing risk of adverse pregnancy outcome should be evaluated prospectively.

Keywords: birth weight; cerebroplacental ratio; perinatal death; stillbirth; uterine artery Doppler.

MeSH terms

  • Adult
  • Cohort Studies
  • Female
  • Fetal Weight
  • Humans
  • Infant, Newborn
  • Laser-Doppler Flowmetry
  • Middle Cerebral Artery / diagnostic imaging*
  • Perinatal Death*
  • Placenta / diagnostic imaging
  • Placental Insufficiency / diagnostic imaging*
  • Pregnancy
  • Pregnancy Trimester, Third
  • Pulsatile Flow*
  • Retrospective Studies
  • Risk Assessment
  • Stillbirth / epidemiology*
  • Ultrasonography, Doppler
  • Ultrasonography, Prenatal
  • Umbilical Arteries / diagnostic imaging*
  • Uterine Artery / diagnostic imaging*