Early twin-to-twin transfusion syndrome: From early gestational physiology to diagnosis and management.

Twin-to-Twin Transfusion Syndrome (TTTS) occurs in about 15 % of monochorionic twin pregnancies, less frequently does it occur prior to 18 weeks of gestation. When occurring early, this severe complication presents unique diagnostic and management challenges. In this review we will focus on the pathophysiological mechanisms underlying early TTTS. We will be emphasizing the role of placental vascular anastomoses and hemodynamic imbalances in disease progression. Advances in imaging techniques allow early diagnosis of the disease, impacting on consultation and clinical decision-making. Current treatment strategies, specifically including fetoscopic laser photocoagulation, are reviewed with a focus on optimizing perinatal outcomes. By integrating insights from fetal physiology, diagnostic innovations, and therapeutic advancements, this review aims to refine clinical management approaches to improve survival and morbidity outcomes for monochorionic twin pregnancies complicated by early TTTS.