CONCLUSION: Oligohydramnios deﬁned as AFI  5th percentile better predicts fetuses at risk for adverse perinatal outcome compared to AFI  5 cm. Pregnancies with AFI  5 cm but  the 5th percentile for gestational age are still at an increased risk for NICU admission. 0002-9378/$ – see front matter • doi:10.1016/j.ajog.2009.10.377 363 Utility of MRI for ultrasound-diagnosed fetal lesions Anthony Shanks 1 , Jennifer Meyer 1 , David Stamilio 1 1 Washington University in St. Louis, St. Louis, Missouri OBJECTIVE: Prenatal MRI as a follow up to ultrasound-diagnosed fetal lesions is common in modern obstetrics. However, MRI is expensive, time consuming, and the beneﬁts in the pregnant population are un- clear. The objectives of the study are to correlate US and MRI fetal ﬁndings and to determine if management is changed based on the MRI results. STUDY DESIGN: A retrospective cohort study of patients presenting for prenatal MRI from 2005-2008. Postnatal information was used as the gold standard to compare the correlation coefﬁcient for antenatal MRI and US. McNemar’s test was used to compare the two modalities. In addition, the impact of MRI diagnosed ﬁndings on patient care was investigated. RESULTS: 109 prenatal MRIs were performed between 2005-2008 and complete information was available for 80. The PPV of MRI was 79% vs. 70% for US (p 0.008). Fetal lesions were further subdivided based on location: intracranial, thoracic, abdominal, skeletal, and other. A statistically signiﬁcant difference was found between the US and MRI diagnosis for intracranial lesions 69% vs. 58% (p 0.005). No difference was found between prenatal US and MRI diagnoses for thoracic, ab- dominal, skeletal, or renal lesions. Twenty (25%) of the 80 total cases referred for MRI were determined to be normal postnatally. CONCLUSION: US diagnosed lesions involving thoracic, abdominal, re- nal, or skeletal pathology do not mandate further investigation with prenatal MRI. Prenatal MRI may be of beneﬁt to intracranial lesions diagnosed by US. Accuracy of Diagnosis by Imaging Technique Location of Lesion (n) MRI PPV (%) US PPV (%) P value Intracranial (36) 25 (69) 21 (58) 0.005 .......................................................................................................................................................................................... Thoracic (9) 8 (89) 7 (78) 0.317 .......................................................................................................................................................................................... Abdominal (20) 17 (85) 16 (80) 0.317 .......................................................................................................................................................................................... Skeletal/NTD (8) 6 (75) 6 (75) 1.00 .......................................................................................................................................................................................... Renal (5) 5 (100) 4 (80) 0.317 .......................................................................................................................................................................................... Other (1) 1 (100) 1 (100) 1.00 .......................................................................................................................................................................................... Total (80) 63 (79) 56 (70) 0.008 .......................................................................................................................................................................................... 0002-9378/$ – see front matter • doi:10.1016/j.ajog.2009.10.378 364 Withdrawn 0002-9378/$ – see front matter • doi:10.1016/j.ajog.2009.10.379 365 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 Anthony Odibo 1 , Yan Zhong 1 , Linda Odibo 1 , Kristina Huster 1 , George Macones 1 , D. Michael Nelson 2 1 Washington University in St. Louis, St. Louis, Missouri, 2 Washington University in St. Louis, OBGYN and Cell Biology & Physiology, St. Louis, Missouri OBJECTIVE: 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 set- tings and the rotational technique (VOCAL). Vascularization index (VI), ﬂow index (FI) and vascularization ﬂow index (VFI) was ob- tained 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 ges- tational 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 RESULTS: The mean placenta volume, VI, FI and VFI were: 41.5cm 3 , 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. CONCLUSION: Placental volume, VI, and VFI in ﬁrst trimester placentas are measures of placental development independent of analyte secre- tion. The correlation of ﬂow index with both PAPP-A and ADAM12s likely reﬂects the key role these molecules play in trophoblast inva- sion. 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. Correlation coefﬁcients and signiﬁcance levels of analytes ADAM12 (p-value) PAPP-A (p-value) -hCG (p-value) Placenta volume 0.06 (0.42) 0.10 (0.17) 0.02 (0.76) .......................................................................................................................................................................................... VI 0.11 (0.16) 0.06 (0.39) -0.013 (0.86) .......................................................................................................................................................................................... FI 0.18 (0.02)* 0.15 (0.04)* -0.008 (0.91) .......................................................................................................................................................................................... VFI 0.12 (0.11) 0.07 (0.38) -0.002 (0.98) .......................................................................................................................................................................................... 0002-9378/$ – see front matter • doi:10.1016/j.ajog.2009.10.380 366 Placental volume measurements early in pregnancy predict adverse perinatal outcomes Nadav Schwartz 1 , Jaclyn Coletta 2 , Sindhu Srinivas 1 , Cara Pessel 2 , Ilan E. Timor 2 , Sam Parry 1 , Carolyn Salaﬁa 3 1 Hospital of the University of Pennsylvania, Maternal and Child Health Research Program; Dept OBGYN, Philadelphia, Pennsylvania, 2 New York University, Obstetrics and Gynecology, New York, New York, 3 Placental Analytics, LLC, Larchmont, New York OBJECTIVE: Effective early predictors of adverse obstetric outcomes are lacking. We sought to determine whether volumetric assessment of the early placenta can predict adverse obstetric outcome. STUDY DESIGN: In this prospective cohort study, we obtained 3D pla- cental volumes at 11-14 weeks. The VOCAL application of 4DVIEW (GE) was used to calculate placental volume (PV). PV was normalized to CRL to yield the placental quotient (PQ=PV/CRL). In addition, we measured the distance from the cord insertion to the nearest placental margin every 45 degrees around the placental circumference (8 mea- surements). The mean of these values, mean cord distance (MCD), is intended to serve as a novel descriptor of the chorionic plate and the centricity of the cord insertion. PQ and MCD were analyzed as pre- dictors of a composite adverse outcome (COMP=SGA [BW10th percentile], PEC, SPTB37 wk, NICU admission). T-tests were used to compare mean values. ROC curves were constructed to determine optimal cut-points for each independent variable. RESULTS: 135 subjects were included. 40 (29.6%) had a composite ad- verse outcome (SGA-23, PEC-7, PTB-4, NICU-14). PV did not vary with maternal age, parity, BMI or ethnicity. Mean PQ (1.08, 0.97-1.19 vs 1.20, 1.15-1.25; p=0.04) and MCD (4.03, 3.85-4.21 vs 4.29, 4.17-4.40; p=0.02) were signiﬁcantly lower in pts with COMP. PQ1.00 conferred an in- creased risk for COMP (OR- 3.5, 1.6-7.34, P0.002), with a speciﬁcity of 77.9% (68.2-85.8) and sensitivity of 50% (33.8-66.2). Similarly, Poster Session II Diabetes, Doppler, Labor, Ultrasound-Imaging www.AJOG.org S142 American Journal of Obstetrics & Gynecology Supplement to DECEMBER 2009