600 RANDOMIZED DOUBLE BLIND COMPARISON OF REMIFENTANIL AND DIAZEPAM FORFETAL IMMOBILIZATION AND MATERNAL SEDATION DURING FETOSCOPIC SURGERYJAN DEPREST1, DOMINIQUE VAN SCHOUBROECK1, LIESBETH LEWI1, MARCO MARCUS2,JACQUES JANI1, CARLO MISSANT3, ROLAND DEVLIEGER1, AN TEUNKENS3,MARC VANDEVELDE3, 1University Hospital Gasthuisberg, Obstetrics andGynecology, Leuven, Belgium, 2AZ Maastricht, Anesthesia, Maastricht,Netherlands, 3University Hospital Gasthuisberg, Anesthesia, Leuven, Belgium

OBJECTIVE: Most fetoscopies are performed under (loco)regional anesthesia,which does not provide fetal immobilization. Transplacental administration ofsedatives may achieve this and comfort the mother. Diazepam (DZP) inducesprofound maternal sedation and incomplete fetal immobilization. We comparedthe efficacy of I.V. remifentanil (REMI), a short acting opioid (umbilical vein/maternal artery ratio 0.88) to that of DZP for maternal sedation and fetalimmobilization.

STUDY DESIGN: Single center randomized double blind trial with 54consecutive women undergoing fetoscopic cord occlusion (n = 12) or lasersurgery for TTTS (n = 42). Following CSE-anesthesia, incremental doses DZP(bolus 5 mg, 5 mg 10 min later and 2.5 mg top ups) or continuous infusionREMI (0.1 mg/kg/min followed by 0.025 bolus top ups). Patients, gynecologistsand attending anesthesiologist were blinded to the sedative used. Maternalsedation (observer alertness score-OAS, need for additional medication),hemodynamics, side-effects as well as fetal hemodynamics and immobilization(Visual Analog Score by ultrasonographer and surgeon, later review ofvideotape by third assessor) were evaluated prior, during and for 60 min aftersurgery. Statistics were by ANOVA testing, and chi-square Fisher exact test forcategorical data. Data are presented as mean G Standard Deviation, medianand interquartile range and percentage of group total.

RESULTS: Four fetuses were excluded because of absence of fetal movementsat baseline. DZP (mean = 14.5 G 4.8 mg) resulted in deeper maternal sedationwithout respiratory depression. REMI (0.115 G 0.020 mg/kg/min) producedadequate maternal sedation with mild but clinically irrelevant respiratorydepression, except in one patient with OAS !4. Fetal immobilizatin occurredfaster and was better but on stimulation the fetus was easily awakened. Thisresulted in more often good surgical conditions (32 % DZP, 92 % REMI),shorter operation times and mothers being less sedated afterwards. Similar doses

SMFM Abstracts S169

598 DEMOGRAPHIC FACTORS ASSOCIATED WITH PATIENTS’ PREFERENCES TO UNDERGOABORTION FOR TRISOMY 21 GEETA SHARMA1, HEATHER T. GOLD2, STEPHENT. CHASEN3, ABIGAIL K. ALT3, LAURENCE MCCULLOUGH4, FRANK A. CHERVENAK5,1Columbia University, Obstetrics and Gynecology, New York, New York,2Weill Medical College of Cornell University, Public Health, New York, NewYork, 3Weill Medical College of Cornell University, Obstetrics and Gynecology,New York, New York, 4Baylor College of Medicine, Medicine, Houston, Texas,5Cornell University Medical Center, Obstetrics/Gynecology, New York, NewYork

OBJECTIVE: The decision to undergo abortion may be related to one’smedical or personal history. We sought to understand demographic factors thatcontribute to a patient’s hypothetical decision to undergo an abortion for DownSyndrome (DS).

STUDY DESIGN: First trimester ultrasound patients with singleton gestationswere prospectively recruited to complete an anonymous, voluntary surveyregarding first trimester screening. Personal demographic and pregnancy historyinformation was obtained and quantified. A 5-point Likert scale was used toassess patients’ preferences regarding pregnancy termination if a diagnostic testrevealed DS. Chi-square and Mann-Whitney U tests were used for statisticalanalysis. Patients were recruited by a physician not involved in their care.

RESULTS: There were 102 women who completed the survey. The median agewas 33 years, and 40 patients were primigravid. Of the multigravidas, 20.6% hada history of voluntary abortion (VTOP) and 22.5% had had a spontaneousabortion. Factors such as maternal age, education level, employment status,infertility, knowledge of someone with DS and intact support systems were notsignificantly associated with patient preferences to have or not have an abortion.However, multigravidas with a history of VTOP were significantly more likely toprefer having another VTOP if test results showed DS (57.1% vs 25.6%,P = .016).

CONCLUSION: There were no reliable factors that predicted a woman’sdecision to undergo termination of pregnancy for Down Syndrome, exceptmultigravidas with a history of VTOP were significantly more likely to choose toundergo an abortion.

599 ASSOCIATION BETWEEN METHOD OF CONCEPTION, CYTOKINES IN CORD BLOOD ANDPREGNANCY OUTCOME GEETA SHARMA1, ANN MARIE BONGIOVANNI2, VICTOR R.ROSENBERG2, SANTOSH VARDHANA3, FRIDA M. FRIDMAN3, ERIN S. SHORENSTEIN3,VLADIMIR RATUSHNY3, DANIEL NGUYEN2, LILLY-ROSE PARASKEVAS3, ROBIN B.KALISH2, STEVEN S. WITKIN4, 1Cornell University, Obstetrics and Gynecology,New York, New York, 2Weill Medical College of Cornell University, Obstetricsand Gynecology, New York, New York, 3Weill Medical College of CornellUniversity, Obstetrics & Gynecology, New York, New York, 4CornellUniversity Medical College, New York, New York

OBJECTIVE: To determine differences in pregnancy outcome between womenwho conceived spontaneously and those who conceived via assisted reproductivetechnology (ART) and to examine the relation between the different outcomesand concentrations of interleukin-1 receptor antagonist (IL-1ra) and interleukin-6 (IL-6) in cord blood.

STUDY DESIGN: Venous cord bloods were collected from 496 deliveries andassayed for IL-1ra and IL-6 by ELISA. Pregnancy outcomes were obtained frompatients’ charts.

RESULTS: 240 of the subjects conceived spontaneously (218 males and 222females) and 59 utilized ART (29 males and 30 females). For both genders,babies conceived via ART had a lower birthweight compared to those fromspontaneous conceptions (P ! .001) Preterm birth, intrauterine growth re-striction (36.7% vs. 8.6%, P = .0001), respiratory distress syndrome (26.7% vs.3.2%, P ! .0001) and infant placement in the neonatal intensive care unit(30.0% vs. 3.8%, P = .0006) occurred at a higher rate only in female infantsconceived by ART as compared to naturally conceived females. Median cordblood IL-1ra levels in ART-conceived females (2.1 ng/ml) were less than half thelevels observed in females from spontaneous conceptions (5.3 ng/ml) (P = .01).IL-1ra levels in the two male subgroups were similar to the levels inspontaneously conceived females. The IL-6 levels in ART-conceived femaleswas also reduced as compared to the other groups, but this did not reachstatistical significance. Mothers who conceived via ART were older than theother women (a mean of 35.0 years vs. 32.7 years, P ! .05). However, there wasno relation between age and the other variables examined.

CONCLUSION: Female infants conceived via ART appear to be at increasedrisk for adverse pregnancy outcome as compared both to ART-conceived malesand spontaneously conceived males and females. Reduced production of botha pro- and an anti-inflammatory cytokine in ART-conceived females maycontribute to this susceptibility.

*Supported by NIH grant 41676.

and number of top ups of ephedrine and phenylephrine were required in bothgroups.

CONCLUSION: REMI provides excellent fetal immobilization and maternalsedation and is immediately reversible. This method of transplacental sedationcould also be applied during other fetal procedures without direct fetal painstimulus (eg MRI).

601 NATURAL HISTORY OF FETAL POSITION DURING PREGNANCY AND RISK OF BREECHDELIVERY JUN ZHANG1, MELISSA PARK1, UMA REDDY2, 1National Institutes ofHealth, Epidemiology Branch, Bethesda, Maryland, 2National Institutes ofHealth, Perinatology Branch, Bethesda, Maryland

OBJECTIVE: Breech presentation is an important contributor to Cesareandelivery. However, the etiology of this complication is poorly understood.Systematically measuring fetal position during pregnancy by ultrasound andfollowing a large number of non-vertex pregnancies to delivery have never beendone. We examined the natural history of fetal position throughout pregnancyand the likelihood of non-vertex delivery by various factors in a large cohortstudy.

STUDY DESIGN: A total of 7249 singleton, low risk pregnant women whoreceived two routine ultrasound exams at 16-22 weeks and 31-35 weeks ofgestation in a previous randomized trial were included, with 16,229 U/S exams(including clinically indicated exams) and delivery information. We examined thedynamic fetal positioning during pregnancy, the likelihood and risk factors fora non-vertex position at 36 weeks of gestation or later. Subjects who received anexternal cephalic version at 36 weeks or later were considered as having a non-vertex position at delivery.

RESULTS: In early pregnancy, approximately half of fetuses had non-vertexposition. The percentage decreased with advancing gestation. By 31 – 35 weeks,13% had non-vertex position. Non-vertex position in early pregnancy had norelationship with non-vertex presentation in late pregnancy. The probabilities ofspontaneous version to vertex position was 79%, 71%, 70%, 66% and 47% at31, 32, 33, 34, and 35 weeks of gestation, respectively. 93 women underwentexternal cephalic version with a success rate of 61%. Nulliparity, previousabortion and smoking during pregnancy were risk factors for non-vertexposition at delivery.

CONCLUSION: Our large cohort study with repeated U/S exams depicts thedynamics of fetal position during pregnancy. Even in late pregnancy, thelikelihood of spontaneous version to vertex position by 36 weeks is relativelyhigh.