18–22 September 2011, Los Angeles, CA, USA Poster abstracts follow-up. Perinatal morbimortality was defined as death or severe neurological damage at 28 days or discharge from NICU. Results: 663 cases were reviewed, with 14%, 37%, 45% and 3% stage 1, 2, 3 and 4 respectively. Median gestational age at surgery was 21 weeks (IQR = 19–22.5). The overall survival of 0, 1 and 2 twins was 16%, 31% and 53% respectively. The overall median gestational age at delivery was 32.5 weeks (IQR = 28.5 – 34) and 37.5 weeks (Kaplan-Meier, 95%CI = 36–39) for spontaneous labor. The cumulative incidence of unexpected complications in ongoing pregnancies increased to 32% (Kaplan- Meier, 95%CI = 27–36%) at 35 weeks and was steady onwards. Concurrently, perinatal morbimortality decreased to < 5% at ≥ 34 weeks. Conclusions: Our data does not support elective preterm delivery in otherwise uncomplicated pregnancies treated by FSLC. How- ever, after 36 weeks, our data may be insufficient to safely consider prolonging pregnancies thereafter. Prevention of complications by elective delivery < 34 weeks would increase perinatal morbimortal- ity. Supporting information can be found in the online version of this abstract. P21.02 Outcome of hydropic Parvo-B19 infected fetuses referred for intrauterine transfusion (IUT) L. De Catte 1 , B. De Becker 2 , R. Devlieger 1 , N. El Handouni 1 , E. Ortibus 3 1 OB-GYN, UZ Leuven, Leuven, Belgium; 2 OB-GYN, St Augustinus, Wilrijk, Belgium; 3 Pediatric Neurology, UZ Leuven, Leuven, Belgium Objectives: To analyse the overall and neurological outcome of fetal Parvo-B19 infection related hydrops referred for in utero transfusion. Methods: Between 2000 and 2010, 21 cases of fetal hydrops diagnosed as Parvo-B19 infection were referred. Sonographic features at admission, hematological parameters at IUT, the number of IUT’s, and pregnancy complications were evaluated. Fetal NMR was proposed to rule out central nervous system anomalies. Gestational age at delivery, birth weight and immediate neonatal condition were evaluated. Neurological outcome was assessed by a pediatric neurologist by means of Bayley scores. Results: Of the 21 referred cases, all showed ascites, cardiomegaly, tricuspid regurgitation and increased PSVACM > 1.5 MoM. Two fetuses died before IUT could be arranged. In 3 other cases, fetal death occurred after the first IUT. Of the remaining 16 cases, 3 couples opted for termination of pregnancy because of cerebral/cerebellar anomalies within 2 weeks after the IUT. The mean hematocrit before IUT was 8.3% (range 4.0–24.%3). The mean number of IUT was 2 (range 1–4). Of the 13 fetuses surviving the IUT’s, 1 additional case was lost in the neonatal period (survival 12/19 = 64%). Mean gestational age at birth was 37 weeks (29 – 40 weeks), and mean birth weight 3005 g (1795 – 3230 g). Fetal MRI, when performed, did not reveal additional brain anomalies. In all cases, hydrops resolved slowly over weeks. Neurological evaluation by Bayley scores of infant development performed in 7 cases were normal. In the remaining 5 neonates, no complications were observed, and general development is normal. Neurological assessment is planned. Conclusions: Parvo-B19 related hydrops fetalis is often associated with fetal death or severe central nervous system abnormalities shortly after IUT. Obstetric and neurological outcome in the surviving fetuses seems favorable. P21.03 The outcomes of prenatally diagnosed sacrococcygeal teratoma M. Lee , H. Won, J. Shim, P. Lee, A. Kim Obstetrics, ASAN Medical Center, Seoul, Republic of Korea Objectives: To evaluate the outcomes of sacrococcygeal teratoma (SCT), and to establish the prenatal counseling guideline for SCT. Methods: A retrospective analysis was undertaken in 21 consecutive fetuses diagnosed with SCT prenatally between September 2000 and December 2010 in Asian medical center. We evaluated postnatal outcomes, according to variable factors, 1) size, 2) subtype, 3) intervention, 4) characteristics of tumor by reviewing the medical records. We excluded the fetuses with associated anomalies. Results: Thirty three fetuses were diagnosed as SCT prenatally. Nine (27%) out of 33 cases were lost to follow-up and 24 cases (73%) were born alive. Among the 24 live births, 3 cases (13%) were confirmed as other diagnosis (fecal impaction, Wilms tumor, and meningomyelocele). The accuracy of diagnosis was 88%. We performed fetal intervention in 7 cases (4 radiofrequency ablation [RFA], 2 shunt, 1 RFA with cyst aspiration). The indication for RFA was rapidly growing mass with high vascularity, and associated with polyhydramnios. The overall survival rate of SCT was 90% (19/21). We could not reveal any effects of variable factors due to the low mortality rate and small sample size. Preterm birth was high in intervention group. There were no fetuses who developed cardiac failure or hydrops. Only one case demonstrated successful regression of tumor after RFA. All other cases were progressively increased with size. Mean diameter of mass at birth was 95 mm (35–230 mm) (141 mm [58–230 mm] in intervention group, 71 mm [35–150 mm] in non-intervention group). Most common complication after postnatal surgery was fecal incontinence (14%, 3/21). Conclusions: The overall survival rate of SCT was high despite of huge mass. The most common postnatal morbidity was fecal incontinence. So we recommend to reassure the parents to continue the pregnancy and treat with proper management postnatally. P21.04 The role of cephalocentesis in the management of the severely hydrocephalic fetus E. Howse 1 , T. Teoh 3 , E. Kelly 1 , D. Chitayat 1 , P. McParland 2 , G. Ryan 1 1 Department of Obstetrics and Gynecology, Maternal-Fetal Medicine, University of Toronto, Toronto, ON, Canada; 2 Department of Fetal Medicine, Obstetrics and Gynaecology, National Maternity Hospital, Dublin, Ireland; 3 Department of Obstetrics & Gynecology, St. Mary’s Hospital, London, United Kingdom Objectives: To review the role of cephalocentesis in the fetus with severe hydrocephalus and to report on perinatal, neonatal and neurodevelopmental outcomes in survivors at two tertiary care centers. Methods: This retrospective descriptive study identified all cases of cephalocentesis at the Fetal Medicine Unit, Mount Sinai Hospital, Toronto, Ontario and the National Maternity Hospital, Dublin, Ireland between 1985 and 2011. Outcome information was obtained from maternal and pediatric charts, procedure, labor and delivery, and autopsy records (in the case of stillborn fetuses). Antenatal ultrasound findings, fetal karyotype, the method and route of cephalocentesis were evaluated. Results: 55 cases of cephalocentsis were identified. The method of cephalocentesis was not standardized. All patients had an antenatal ultrasound that diagnosed severe hydrocephalus. The mean gestational age at diagnosis and delivery were 30 and 35 weeks respectively. Thirty four of 55 (62%) underwent induction of labor. Two patients were delivered by cesarean section. Twenty three underwent spontaneous vaginal delivery, 21 breech vaginal Ultrasound in Obstetrics & Gynecology 2011; 38 (Suppl. 1): 168–281 237