543 DETERMINING A CUT-OFF FOR FETAL LUNG MATURITY WITH LAMELLAR BODYCOUNT TESTING MARY BETH JANICKI1, LISA DREISS1, JAMES EGAN2, CAROLYNZELOP1, 1Saint Francis Hospital and Medical Center, Hartford, Connecticut, 2Uni-versity of Connecticut, Farmington, Connecticut

OBJECTIVE: A lamellar body count (LBC) �50,000 has been suggested to indi-cate fetal lung maturity (FLM) (Obstet Gynecol 2001;97;318-20). The purpose ofthis study was to determine the LBC cut-off for FLM at our institution.

STUDY DESIGN: We queried our antenatal database for patients who underwentamniocentesis and LBC testing for FLM from 2001-2007. We included patients deliv-ered between 35 and 38 weeks gestation with testing � 7 days from date of delivery andcomplete medical records. We excluded twins, fetal anomalies and delivery for ruptureof membranes. Data was analyzed for sensitivity and specificity of prediciting respira-tory distress (RDS) and plotted on a receiver-operator curve (ROC).

RESULTS: There were 211 patients that met study criteria. Of these 111 werediabetics. Five neonates experienced RDS. The ROC is shown below. All 5 cases ofRDS were born to non-diabetic mothers and had LBC values � 72,000. At this valuethe sensitivity is 100% with a false positive rate of 18% and a p value of 0.0003.

ROC for RDS using LBCCONCLUSION: Our results question the suggested 50,000 cut-off and may raise

the need for institution-specific determination of LBC for FLM.

0002-9378/$ - see front matterdoi:10.1016/j.ajog.2007.10.545

544 USE OF THE MATERNAL SERUM SCREEN TO PREDICT NEONATAL BIRTH WEIGHTABNORMALITIES AMONG PREGNANT DIABETICS MEREDITH WILLIAMS1, HAONGUYEN1, DENA TOWNER1, 1University of California, Davis, Ob/Gyn, Sacramento,California

OBJECTIVE: The maternal serum screen (MSS) has been used to estimate riskfor Trisomy 21, Trisomy 18, neural tube defects and Smith Lemli Opitz syndrome.Our goal was to determine if its use could be expanded to predict neonatal birthweight abnormalities among pre-gestational and gestational diabetics.

STUDY DESIGN: An IRB approved, retrospective, cohort study was performedreviewing the birth weight percentiles among all diabetic patients delivering at theUniversity of California, Davis between January 2001 and June 2006. We evaluatedassociations with large for gestational age (LGA) and small for gestational age(SGA), All patients who underwent MSS screening and were confirmed diabeticwere eligible. Bivariate analysis was performed using chi-square. Multivariate anal-ysis was performed using logistic regression.

RESULTS: Four hundred ninety eligible subjects were identified out of all de-liveries occurring during the specified time period. Among gestational diabetics,�HCG � 3 MoM and multiparity were independent risk factors for LGA neonates(see Table 1). Estriol � 0.7 MoM was a risk factor for SGA neonates. Amongpre-gestational diabetics, multiparity alone was associated with LGA neonates (OR5.38, CI 1.33 - 21.78), whereas African American race was a predictor for SGAneonates (OR 9.84, CI 1.33 - 73.15).

Risk Factor OR 95% CI Outcome

�HCG � 3 MoM 7.23 2.09-25.06 LGAMultiparity 5.02 1.95-12.94 LGAEstriol � 0.7 MoM 3.51 1.52-8.11 SGA

CONCLUSION: Among gestational diabetics, �HCG � 3 MoM is a predictor forLGA neonates. Estriol � 0.7 MoM is a risk factor for SGA neonates. Pre-gestationaldiabetes increased the risk for SGA neonates by a factor of 5 over the baseline inAfrican American subjects. The MSS is not an effective predictor for birth weightabnormalities among pregestational diabetics.

0002-9378/$ - see front matterdoi:10.1016/j.ajog.2007.10.546

545 USE OF THE MATERNAL SERUM SCREEN TO PREDICT ADVERSE MATERNALOUTCOMES AMONG PREGNANT DIABETICS MEREDITH WILLIAMS1, HAO NGUYEN1,DENA TOWNER1, 1University of California, Davis, Department of Ob/Gyn, Sacra-mento, California

OBJECTIVE: The maternal serum screen (MSS) has been used to estimate riskfor selected neonatal chromosomal and anatomic outcomes as well as limited ma-ternal outcomes. We attempted to determine if the MMS could be used to predictadverse maternal outcomes among pregnant diabetics.

STUDY DESIGN: An IRB approved, retrospective, cohort study was performedreviewing the maternal pregnancy and delivery outcomes among all diabetic pa-tients delivering at the University of California, Davis between January 2001 andJune 2006. All patients who underwent MSS screening and were confirmed diabeticwere eligible. Bivariate analysis was performed using chi-square. Multivariate anal-ysis was performed using logistic regression.

RESULTS: Four hundred ninety eligible subjects were identified out of all de-liveries occurring during the specified time period. Among pregnant diabetics thevariations in the MSS were associated with post partum hemorrhage, shoulderdystocia, oligohydramnios, pre-term delivery, and pre-eclampsia (See Table 1).These relationships were present regardless of type of diabetes (pre-gestational vs.gestational).

Risk Factor OR 95% CI Outcome

�HCG 2-2.99 MoM 4.88 1.28-18.61 Post partum hemorrhage�HCG � 3 MoM 28.04 1.76-445.89 Shoulder dystocia�HCG � 3 MoM 6.34 1.67-24.09 OligohydramniosAFP 1-1.99 MoM 3.03 1.31-7.02 Pre term deliveryAFP 2-2.99 MoM 7.35 1.14-47.3 Pre term deliveryEstriol � 0.7 MoM 2.39 1.04-5.50 Pre-eclampsia

CONCLUSION: Adverse maternal pregnancy and delivery outcomes are associ-ated with abnormal values of the MSS. Surprisingly, AFP values that are still in theaccepted normal range are associated with pre-term delivery. Elevated �HCGshows the greatest association with adverse outcomes. We hypothesize that earlyabnormalities in placental function, represented by the elevated �HCG contributesto the observed relationships.

0002-9378/$ - see front matterdoi:10.1016/j.ajog.2007.10.547

546 CONTEMPORARY OUTCOMES WITH THE LATEST 1,000 CASES OF MULTIFETALPREGANCY REDUCTION(MPR) JOANNE STONE1, LAUREN FERRARA1, JACQUELINEKAMRATH2, JOELLE GETRAJDMAN3, RICHARD BERKOWITZ4, ERIN MOSHIER5, KEITHEDDLEMAN6, 1Mount Sinai School of Medicine, OBGYN, New York, New York,2Mount Sinai School of Medicine, OBGYN, , New York, 3Mount Sinai School ofMedicine, , New York, 4Columbia University, New York, New York, 5Mount SinaiSchool of Medicine, Department of Community and Preventive Medicine, NewYork, New York, 6Mount Sinai School of Medicine, New York, New York

OBJECTIVE: To report on the outcome of MPR in the most up-to-date largestsingle center experience with this procedure.

STUDY DESIGN: 1,000 consecutive cases of MPR performed at the Mount SinaiMedical Center between the years1999 to 2006 were identified. Pregnancy out-comes were obtained from chart review. Differences in proportions were evaluatedby Chi-Square, Cochran-Armitage test for trend or two-tailed Fisher exact test asappropriate.

RESULTS: Outcomes were available for 841 cases for a follow-up rate of 84.1%.95.2% of patients delivered after 24 wks, for a complete loss rate of 4.7%. This wasnot significantly different from the loss rate of 5.9% reported in our initial 1,000MPR’s, p�0.28. There was a significant trend toward decreasing loss rates withdecreasing starting numbers (11%, 5.5%, 5.1% and 2.1% for start no. of 5�, 4, 3and 2), p�0.04, There was no significant difference is loss rate for MPR to twins vs.singletons, 5.3% and 3.8%, p�0.35. Table 1 shows no significant differences in lossrates between twins and singletons at the same starting numbers. Mean GA of loss(16.7 and 19.7 wks,, and mean GA at delivery (38.0 and 35.2 wks) were significantlyearlier for MPR to 1 vs, 2, p�0.03 and p�0.001. Starting number did not affect GAat delivery, although a significant inverse correlation with birth weight was seen.There was significant increase in preterm delivery (PTD) � 32 weeks for twincompared to singletons, 4.0 vs. 11 %, p� 0.05, Higher starting numbers resulted inearlier delivery in patients reduced to twins (0.002) but not for those reduced tosingletons p�0.13.

CONCLUSION: Loss rates after MPR have remained stable at 4.7%. Interestingly,reduction to a singleton is not associated with lower loss rates, although is associ-ated with lower rates of PTD.

Loss rate based on starting numbers in MPR to twins and singletons

Starting number MPR to twins (%) MPR to singleton (%)

5� 12.1 04 5.8 4.03 4.5 6.12 2.1

0002-9378/$ - see front matterdoi:10.1016/j.ajog.2007.10.570

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S158 American Journal of Obstetrics & Gynecology Supplement to DECEMBER 2007