Deferred cord clamping in twin pregnancies: benefit, risk, or missed opportunity? A narrative review

Deferred umbilical cord clamping enhances placental transfusion and is associated with improved outcomes in preterm infants. Following lung aeration and prior to umbilical cord clamping, the increase in pulmonary blood flow contributes to establishing blood volume within the pulmonary vascular bed, which constitutes the mechanism of physiology-based cord clamping. While the benefits of deferred cord clamping have been well described in singleton deliveries, evidence in twin pregnancies remains limited. This is particularly relevant for monochorionic twins, who share a placental circulation and may be at risk of inter-twin transfusion. This narrative review summarizes and critically appraises the available literature on deferred cord clamping in twin pregnancies, with particular emphasis on monochorionic twins. We highlight potential benefits, risks, and current knowledge gaps. Individual Participant Data meta-analyses and adequately powered studies are needed to better evaluate outcomes in multiple gestations, including long-term neurodevelopment.