607 FETAL BLOOD SAMPLING: IS INTRAHEPATIC VEIN FETAL BLOODSAMPLING AS SUCCESSFUL AS PERCUTANEOUS UMBILICAL CORDBLOOD SAMPLING? CYNTHIA HOLCROFT1, ABIMBOLA AINA-MUMU-NEY1, RITA DRIGGERS1, NANCY HUEPPCHEN1, EVA PRESSMAN1, KARINBLAKEMORE1, 1Johns Hopkins University, Gynecology & Obstetrics,Baltimore, MD

OBJECTIVE: To determine the success rate and variables that alter successin intrahepatic vein fetal blood sampling (IHV) and percutaneous umbilicalcord blood sampling (PUBS).

STUDY DESIGN: IRB-approved retrospective chart review of attemptedfetal blood samplings done at our institution by IHV or PUBS from 7/87-8/03.Data abstracted include gestational age at procedure, placental location,presence of hydrops or ascites, attempted procedure, and success of procedure.Data analyzed by t-test, Fisher’s exact, and chi-square with P < 0.05 consideredsignificant.

RESULTS: We identified 187 attempted cases: 97 IHV, 75 PUBS, and 15combined procedures. 96 of 112 (86%) of attempted IHV were successful vs 70of 90 (78%) of attempted PUBS (P = 0.14). In 5 of 96 (5%) successful IHV cases,PUBS was first tried unsuccessfully; in 8 of 70 (11%) successful PUBS cases, IHVwas first tried unsuccessfully (P = 0.16). Placental location was statisticallydifferent in the successful samplings. For successful IHV, placental location wasanterior 47%, posterior 43%, and fundal/lateral 10%. For successful PUBS,placental location was anterior 67%, posterior 21%, and fundal/lateral 12%(P = 0.01). There were 27 of 187 (14%) attempted cases performed at #22weeks’ gestation; of these, 8 of 9 (89%) of IHV were successful vs 15 of 18 (83%)of PUBS (P = 1.0). There was no statistical difference in gestational age,hydrops, or ascites between either attempted or successful IHV and PUBS.

CONCLUSION: IHV is as successful as PUBS in obtaining an adequate fetalblood sample. In our series IHV was slightly more successful than PUBS,although this difference did not reach statistical significance (86% vs 78%,P = 0.14). Gestational age did not contribute to a difference in success rate. Forsuccessful procedures the placenta was posterior in 43% of IHV versus 21% ofPUBS. IHV should be considered a strong alternative to PUBS for fetal bloodsampling, particularly in cases with posterior placentas.

608

609 DIRECT EVALUATION OF FETAL CELL TRAFFICKING WITH FETAL DNAPCR AFTER CORDOCENTESIS (PUBS) GEETA SHARMA1, WILLIAM F.REED2, TZONG-HAE LEE2, MICHAEL FEUERSTEIN3, ROBIN B. KALISH1,JAMES B. BUSSEL3, 1Weill Medical College of Cornell University, Obstetricsand Gynecology, New York, NY 2Blood Centers of the Pacific, Irwin Center,San Francisco, CA 3Weill Medical College of Cornell University, Pediatrics,New York, NY

OBJECTIVE: As other studies have indirectly assessed feto-maternalhemorrhage after invasive procedures, we sought to directly assess if PUBSenhances feto-maternal cell trafficking, resulting in increased levels of cell-freeand cell-associated fetal DNA in the maternal circulation.

STUDY DESIGN: Maternal serum samples were prospectively obtainedbefore and after PUBS and a 1-cc aliquot of fetal blood was obtained for studypurposes, with IRB approval. Serial follow-up maternal serum samples werecollected 1 hour to 3 months post PUBS. Maternal and fetal DNA were typed byamplification using PCR primers specific for an HLA-DR panel. The markerallele unique to the fetus was identified, and all serial maternal samples wereamplified for this informative allele using real-time kinetic PCR.

RESULTS: 8 patients underwent PUBS, 6 for diagnostic and 2 fortherapeutic purposes. Fetal genotyping was successful for 5 of the 8 fetuses,yielding 7 samples as one patient underwent 3 procedures. Placental locationwas anterior in 3 patients and posterior in 2 patients. The placental end of theumbilical cord was the site of sampling, and all procedures were performed withone attempt within 5-30 minutes. In 2 of 7 plasma samples (cell-free fetal DNA)and in 3 of 7 whole blood samples (cell-associated fetal DNA) 1-3 genomicequivalents/10 lL (ge/10ll) were detectable pre PUBS. However, the post-PUBS amounts in each sample, 5-6 and 1-5 (ge/10ll), respectively, did notsignificantly differ, P = NS, even though maternal blood was collectedapproximately 1 hour post PUBS.

CONCLUSION: In this small series, there was no substantial increase indetectable fetal DNA in the maternal circulation, either cell-free or cell-associated, following the PUBS procedure, regardless of placental location,indication for PUBS, and number of times of fetal sampling. Larger series areneeded to investigate if invasive antenatal procedures exacerbate maternalimmunization through mechanisms other than cell exchange.

610 ENDOTHELIAL PROGENITOR CELLS DERIVED FROM HUMANUMBILICAL CORD BLOOD SHIN-YOUNG KIM1, JIN-WOO KIM1, SO-YEON PARK1, HYUN-MEE RYU2, 1Samsung Cheil Hospital, SungkyunkwanUniversity, Laboratory of Medical Genetics, Seoul, South Korea 2SamsungCheil Hospital, Sungkyunkwan University, Department of Obstetrics andGynecology, Seoul, South Korea

OBJECTIVE: Endothelial progenitor cells (EPC) play an important role invarious pathophysiological processes. They participate in angiogenesis andarteriogenesis, thus being functionally important in vascular repair. In vitrodevelopment of the EPC from human umbilical cord blood is not wellestablished. Therefore, we studied for the presence of EPC among umbilicalcord blood cells.

STUDY DESIGN: Mononuclear cells (MNC) were isolated from humanumbilical cord blood by density gradient centrifugation and were cultured infibronectin-coated plates for 14 days. The cells were characterized asendothelial-specific markers including von Willebrand factor (vWF), PECAM-1, and Flk-1 via immunocytochemistry. They also were identified as P1H12(CD146), CD14, and CD45 via flow cytometry and as Flt-1, eNOS, VEGFR-2,VE-cadherin, and Tie-2 by reverse-transcriptase polymerase chain reaction(RT-PCR).

RESULTS: Selected MNC acquired an endothelial phenotype and stainedpositive with vWF, PCAM-1, and Flk-1. Expression of CD45 and CD14 graduallydecreased, while endothelial cell marker P1H12 increased over time. The cellsalso expressed Flt-1, eNOS, VEGFR-2, and VE-cadherin as assessed by RT-PCR,but did not express Tie-2.

CONCLUSION: These data indicate that MNC population derived fromhuman umbilical cord blood consists of endothelial progenitor or stem cellswith the capacity to differentiate into endothelial cells. To find the clinicalpotential of EPC for vascular regeneration and therapy, investigations of EPC areindispensable.

Volume 189, Number 6Am J Obstet Gynecol

SMFM Abstracts S225

2D AND 3D ULTRASOUND-GUIDED ENDOSCOPIC UMBILICAL CORDLIGATION WITH BIPOLAR CAUTERY IN TWIN AND TRIPLETMONOCHORIONIC GESTATIONS BRUCE YOUNG1, COURTNEY D.STEPHENSON1, ANDREI REBARBER1, ASHLEY ROMAN1, ANDREW P.MACKENZIE1, VICTORIA MINIOR1, NIKKI KOKLANARIS1, JEANINEMULHOLLAND1, ILAN TIMOR-TRITSCH1, 1New York University, Obstet-rics and Gynecology, New York, NY

OBJECTIVE: To review our experience with a minimally invasive techniquefor umbilical cord ligation as a method of selective feticide.

STUDY DESIGN: 7 cases of monochorionic gestation where selectivefeticide was performedwere identified from 2000 to present. There were two setsof triplets and five sets of twin gestation in the study cohort. Umbilical cordligation was performed using a 3-mm bipolar cautery (Everest) and ultrasoundguidance (GE Voluson 730 Expert, ATL 5000). Coagulation was accomplishedusing 40-50 Watts current lasting for 30-60 seconds in 3 separate areas of thecord. The cord was observed for absence of flow using Power flow Dopplertechnology to complete the procedure. Endoscopic evaluation pre and postligation was performed using a 2-mm endoscope (Storz). 4D ultrasoundtechnology was used to enhance operative technique in 3 cases.

RESULTS: The mean gestational age at cord ligation was 20 weeks (range17-22). Mean interval from intervention to delivery was 11.8 weeks (range 5-21)in the twin gestations. The triplet gestations are both undelivered with viabledichorionic twin gestations at 25 and 20 weeks. All the procedures weretechnically successful. All fetuses not selected for ligation survived theprocedure. There were no intrauterine fetal demises or procedure-associatedleakage of fluid. 2 patients delivered at term, 1 delivered at 33 weeks afterPPROM, 1 patient with a history of an abruption in a prior pregnancy and factor5 Leiden deficiency delivered at 31 weeks after another abruption, and 1 hadPPROM at 26 weeks with neonatal demise.

CONCLUSION: In monochorionic multiple gestation with one abnormalfetus, fetoscopic cord ligation may be performed to salvage the normal fetus orfetuses. Endoscopic umbilical cord ligation can be accomplished in a minimallyinvasive manner with ultrasound guidance in both twin and triplet mono-chorionic pregnancies.