Twin pregnancies inherently carry a higher risk, with the placenta playing a crucial role in determining outcomes. Compared to singleton pregnancies, structural features of the placenta that more frequently contribute to complications include reduction in its size, some characteristics of umbilical cords insertion including abnormalities, proximity and concordance, the pattern of vascular anastomosis, and the distribution of placental sharing. The interaction between placental size, vascular architecture, and metabolic function highlights the complexity of managing monochorionic (MC) and dichorionic (DC) pregnancies. Advances in imaging, molecular biology, and biomarker research provide promising opportunities for improving prediction and intervention strategies, ultimately leading to better maternal and neonatal outcomes.