Twin-to-twin transfusion syndrome: As an obstetric emergency

Abstract

The incidence of multiple births has increased dramatically due to the increasing application of assisted reproductive techniques and advanced maternal age. Twinℝtoℝtwin transfusion syndrome (TTTS) occurs in about 15 % of monochorionicℝdiamniotic twin pregnancies. The syndrome is caused by unbalanced blood flow through vascular placental anastomoses between the twin fetuses. It presents sonographically as an oligohydramniosℝpolyhydramnios sequence hence also known as TOPS sequence. Early diagnosis of a twin pregnancy and establishing the chorionicity by 8ℝ9 weeks helps plan a protocol for individual patient monitoring and followℝup. Timely detection and treatment of TTTS before severe complications such as preterm prelabor rupture of membranes, very preterm delivery (24ℝ32 weeks of pregnancy), fetal hydrops, or single fetal demise occur helps to save many fetal lives. As the symptoms and staging of TTTS are clearly defined, patient education, accurate and early determination of chorionicity, followed by the first trimester scan and targeted serial fortnightly scans make the syndrome, if present, easy to diagnose. Early diagnosis is the key to effective management. Ultrasound and fetoscopy-guided identification and ablation of the vascular placental anastomoses have revolutionized the management of TTTS ensuring higher perinatal survival rates, more advanced gestational age at delivery, and better neurological outcome in the surviving twins.