Pregnancies complicated by Twin-Twin transfusion syndrome: outcome and long-term neurological follow-up.

OBJECTIVE: To relate prenatal data of monochorionic pregnancies complicated by Twin-Twin transfusion syndrome (TTTS) with survival rates and neurological morbidity. STUDY DESIGN: Thirty-two cases of TTTS underwent biweekly ultrasound examinations. Amnioreduction was the standard of care. Mortality and neurological morbidity were evaluated; the children had neurodevelopmental follow-up with a mean follow-up time of 24 months. RESULTS: Ten out of 32 pregnancies terminated before 24 weeks of gestation, six after induction and four after spontaneous abortion. Among the 22 pregnancies followed up after 24 weeks, the overall survival rate at 28 days was 70% (31/44) with 10 intrauterine deaths including three cases of single selective terminations, and with three neonatal deaths. Eighteen out of 31 babies (58%) had a normal neurological development, eight cases had major and five cases minor neurological disabilities. Neonatal survival was not related to gestational age at diagnosis, number of amnioreductions or weeks at delivery. Absence of end diastolic flow in the umbilical artery, either in the donor or the recipient twin, and birth weight <1000 g were both associated with a higher perinatal mortality. Number of amnioreductions (>2) and birth weight <1000 g were both associated with abnormal neurological follow-up. CONCLUSION: In TTTS, absent end diastolic flow in the umbilical artery and birth weight can predict perinatal survival; neurological development is correlated with number of amnioreductions and birth weight.