Third trimester fetoscopic laser ablation of type II vasa previa.

Objective. Vasa previa is associated with increased perinatal morbidity and mortality because of fetal exsanguination at time of membrane rupture. We report our experience in the treatment of type II vasa previa via in utero laser ablation in the third trimester. Methods. Two cases of type II vasa previa were identified via endovaginal ultrasound in the second trimester and treated via third trimester fetoscopic laser ablation. Results. In case 1, fetoscopic laser ablation of the vasa previa was performed without complication at 28 3/7 weeks' gestation as a prophylactic measure. The patient delivered at 33 3/7 weeks' gestation after rupture of membranes without sequelae with good perinatal outcome. In case 2, expectant management of twins with a vasa previa was planned. However, significant cervical shortening and funneling was documented at 30 5/7 weeks', and the risk of membrane rupture was deemed relatively high. As a therapeutic alternative to outright preterm delivery, the patient underwent uncomplicated laser ablation of the vasa previa. Delivery occurred at 34 3/7 weeks' after rupture of membranes, and the twins did well. Conclusions. We suggest that type II vasa previa can be definitively treated in utero by laser photocoagulation in the third trimester. Ablation of the vasa previa may be performed prophylactically or as a therapeutic measure to delay delivery if symptoms of preterm labor and/or cervical shortening develop. [ABSTRACT FROM AUTHOR]