[Surgical treatment of twin-to-twin transfusion syndrome: coagulation of anastomoses with a Nd:YAG laser, under endosonographic control. Forty four cases].

Twin to twin transfusion syndrome occurs in 15% of monozygotic twin pregnancies and is characterized by a hemodynamic imbalance between the two fetuses. Survival is about 10% with expectant management. Our aim is to coagulate the placental vascular anastomoses joining the two fetal circulations on the placenta in order to prevent the consequences on the survivor when one dies in utero. Between November 1993 and April 1996, 44 patients were referred with severe twin to twin transfusion syndrome at less than 28 weeks' gestation. Nd:YAG laser coagulation of the placental vessels crossing the interamniotic membrane was performed under sono-endoscopic control. Forty-one patients have completed their pregnancy and 3 are continuing uneventfully in the third trimester. Fifteen patients (36.5%) delivered 2 healthy infants who survived the neonatal period and are developing normally. Sixteen patients (41.5%) delivered one infant developing, normally after the death of the co-twin in the perinatal period. In ten cases (22%) both twins died in the perinatal period. Among the survivors, 3 (9%) present with neurological handicap at a median age of 9 months. Around 75% (31/41) pregnancies complicated by twin to twin transfusion and treated by fetoscopy delivered at least one healthy baby. These data confirm the feasibility of the technique and that morbidity in-the survivors is relatively low.