During intrauterine life, the fetus is connected to the mother via the placenta; with birth, the extrauterine adaptation process begins. The first six hours after birth are defined as the "adaptation period" for the newborn and consist of three stages. In this process, the first reactive period is particularly critical because the initial assessments determine the newborn's well-being. All organs, especially the respiratory and cardiovascular systems, are rapidly activated, and adaptation parameters are monitored. Evidence-based care interventions applied by midwives during this period directly affect the newborn's physiological stability and long-term health. The timing of umbilical cord clamping is a decisive factor in this adaptation. The World Health Organization recommends waiting at least 1 minute after birth for term and stable preterm infants, ideally with a delay of 1-3 minutes for clamping. Blood flow from the placenta to the baby continues for the first few minutes after birth. Therefore, not clamping the umbilical cord until 2-3 minutes have passed or until the cord pulse has completely stopped provides a physiological blood transfer. In this process, defined as "placental transfusion," a large portion of the blood passes to the baby within the first 3 minutes, contributing to an increase in circulatory volume and hemoglobin levels. In premature infants, stem cell transfer reduces complications and provides long-term benefits. In addition, this practice increases venous return, supporting heart filling and facilitating cardiorespiratory transition. In infants who undergo delayed clamping, oxygen saturation rises faster and irregular heartbeats are less common.