Intrauterine growth retardation in twin-twin transfusion syndrome

Abstract

RUBEN QUINTERO, EFTICHIA KONTOPOULOS, PATRICIA BORNICK, University of South Florida, Obstetrics & Gynecology/Maternal Fetal Medicine, Tampa, Florida OBJECTIVE: Intrauterine growth restriction (IUGR), defined as an estimated fetal weight !10th percentile, can coexist with twin-twin transfusion syndrome (TTTS). The purpose of this study was to assess the outcome of TTTS patients treated with Selective Laser Photocoagulation of Communicating Vessels (SLPCV) relative to the presence of IUGR. STUDY DESIGN: The database of all TTTS patients treated with SLPCV between July 1997 and June 2005 was queried for the concomitant diagnosis of IUGR. Pre-operative variables included gestational age at surgery (GASx), Stage, and absent end-diastolic velocity in the umbilical artery (UA-AEDV) of the IUGR twin. Outcome variables included gestational age at delivery, perinatal survival, survival of the IUGR twin. Surgeries were conducted under IRB approved protocols and all patients signed informed consent. RESULTS: SLPCV was performed in 449 patients during the study period. IUGR was present in 48% of donors. The median GASx was significantly higher in the IUGR group (19.6 weeks vs. 21.3 weeks, p !.001). IUGR differed significantly with Stage (34%, 41%, 59%, 50%, for Stages I, II, III, and IV, respectively, p !.001). IUGR donors were more likely to have UAAEDV (42.2% vs. 23.5%, p!.001). However, survival of at least one fetus (85.8% vs. 87.1%) or of the IUGR donor (63% vs. 75%) was no different between IUGR and non-IUGR groups, respectively. Survival analysis showed no difference in the gestational age at delivery between the two groups (median 33.0 vs. 33.1, IUGR vs. non-IUGR groups). CONCLUSION: IUGR affects approximately 50% of all TTTS patients and is associated with a higher incidence of UA-AEDV. Despite the handicap, overall perinatal survival and, in particular, survival of the IUGR fetus is no different between IUGR and non-IUGR TTTS patients treated with SLPCV. Long term studies on the outcome of IUGR donors are warranted to assess the merit of SLPCV in this subset of TTTS patients.