444: Outcomes of laser photocoagulation for feto-fetal transfusion syndrome in dichorionic-triamniotic triplet gestations as compared to monochorionic-diamniotic twins

pressing its function. The aim of our analysis was to evaluate the potential role of placental dysfunction, defined by values of PlGF, sFlt-1 and sFlt-1/PlGF ratio, in the pathogenesis of IUGR. STUDY DESIGN: A case-control study collecting 90 fetal and maternal serum samples from singleton pregnancies was performed at our Institution between 2005 and 2007. Pregnancies complicated by presence of IUGR (18 mothers and their own newborns IUGR group) were compared to controls with normally grown fetuses (27 mothers and their own babies NORMAL GROWTH group). Mann Whitney U test was used for statistical analysis, with p .05 considered significant. RESULTS: The Table and Figure show results for the analysed markers in maternal and fetal serum. sFlt-1 value was higher in serum of mothers with a pregnancy complicated by IUGR than of patients with normally grown fetuses, whereas no differences were found between these 2 groups in fetal serum. PlGF showed a lower level in IUGR than in NORMAL GROWTH group both in maternal and in fetal samples. sFlt-1/PlGF ratio displayed the same trend of sFlt-1. CONCLUSION: Theresultsofourstudysupport thepivotal roleofplacental dysfunction in determining IUGR. PlGF appeared to be the most powerful marker for identifying this fetal disease, both in the maternal and in the fetal compartment. 444 Outcomes of laser photocoagulation for feto-fetal transfusion syndrome in dichorionic-triamniotic triplet gestations as compared to monochorionic-diamniotic twins Pedro Argoti, Ramesha Papanna, Michael Bebbington, Nahla Khalek, Ahmet Baschat, Anthony Johnson, Kenneth Moise University of Texas Health Science Center at Houston, Department of Obstetrics, Gynecology, and Reproductive Sciences; Houston, TX,, Houston, TX, Yale University, Ob/Gyn & Reprod Sci, New Haven, CT, The Children’s Hospital of Philadelphia, The Center for Fetal Diagnosis and Treatment, Philadelphia, PA, University of Maryland School of Medicine, Obstetrics, Gynecology, and Reproductive Sciences, Baltimore, MD OBJECTIVE: To compare the outcomes of dichorionic-triamniotic (DC,TA) triplet gestations with the outcomes of a paired cohort of monochorionic-diamniotic twin (MC,DA) gestations undergoing laser photocoagulation of placental anastomosis for treatment of fetofetal transfusion syndrome. STUDY DESIGN: All DC,TA triplets treated by at 3 referral centers were included; a matched cohort group of MC,DA twin gestations affected by feto-fetal transfusion syndrome were used for comparison. 16 triplet cases and 32 twin controls were matched for demographic variables including maternal age, race, smoking status, BMI; fetal variables including gestational age at the time of the procedure, weight discrepancies, presenting Quintero stage, presenting DVP in donor and recipient, Doppler abnormalities, placental location and operative variables including operative time, cannula diameter and use of Solomon technique, amnioreduction and amnioinfusion. The Chi Square statistical test was used to compare categorical variables and the unpaired t-test to compare equality of means. Results with a p value 0.05 were considered statistically significant. RESULTS: Appropriate matching was confirmed by the absence of statistical differences between compared variables. All of the “singleton” fetuses in the triplet gestations survived to birth and to the end of the neonatal period (Table). CONCLUSION: This study shows an increased general risk of prematurity after laser treatment for DC, TA triplets compared to MC, DA twin (three-week difference). A shorter interval from surgery to delivery in triplets also confirms the increased risk. Despite the increased prematurity risk in triplets, no difference in survival to birth or neonatal survival was found after laser. These findings have important implications regarding long term outcomes when counseling patients with dichorionic-triamniotic triplet gestations considering laser therapy. Statistical significant markers’ level in maternal and fetal serum