365: Correlation between three-dimensional placental volume and vasculature indices with maternal serum A-disintegrin and metalloproteinase (ADAM12s), -HCG and PAPP-A in the first trimester


      We tested the hypothesis that first-trimester 3-D placental volume and vasculature indices correlate with the maternal serum analytes, A-disintegrin and Metalloproteinase (ADAM12s), PAPP-A and -hCG.

      Study Design

      Placental volume and vasculature was determined in a prospective cohort study of 219 women at 11-14 weeks' gestation. Placental volume was obtained using pre-established ultrasound settings and the rotational technique (VOCAL). Vascularization index (VI), flow index (FI) and vascularization flow index (VFI) was obtained from 3-D power Doppler histograms. ADAM12s, -hCG and PAPP-A levels were measured using the immunofluorometric assays, and values were converted to multiples of the medians for the gestational age. The relationship between the placental volumes or vasculature indices and each serum analyte was assessed using linear regression and Pearson's or Spearman's correlation coefficients as appropriate


      The mean placenta volume, VI, FI and VFI were: 41.5cm3, 22.6, 42.8, and 7.4, respectively. Placental volume, VI, and VFI were not correlated with any of the three serum analytes (Table). FI showed a weak but significant correlation with ADAM12s and PAPP-A levels but not hCG.
      Tabled 1Correlation coefficients and significance levels of analytes
      ADAM12 (p-value)PAPP-A (p-value)β-hCG (p-value)
      Placenta volume0.06 (0.42)0.10 (0.17)0.02 (0.76)
      VI0.11 (0.16)0.06 (0.39)−0.013 (0.86)
      FI0.18 (0.02)*0.15 (0.04)*−0.008 (0.91)
      VFI0.12 (0.11)0.07 (0.38)−0.002 (0.98)


      Placental volume, VI, and VFI in first trimester placentas are measures of placental development independent of analyte secretion. The correlation of flow index with both PAPP-A and ADAM12s likely reflects the key role these molecules play in trophoblast invasion. The data suggest that placental volume, VI, VFI and analyte secretion can be used in combination to develop prediction models for adverse pregnancy outcomes in the second half of pregnancy.