RESUMO
OBJECTIVE: Umbilical cord blood is an effective alternative to bone marrow as a source of hematopoietic stem cells for transplantation. But the amount of collected umbilical cord blood and its contents are limited and obtaining an adequate volume of umbilical cord blood is essential for successful transplantation. The aim of this study was to identify factors that influence the volume of umbilical cord blood. METHODS: A retrospective analysis of the maternal, neonatal and placental factors that were obtained by medical record review was conducted. The variables that were evaluated for this study were mother's age, parity, gestational age, presence of maternal diabetes mellitus, route of delivery, multiple births, neonatal sex and birth weight, and placental weight. Total 484 deliveries were evaluated from March 2003 to April 2004. The statistical significance of observed differences was calculated using t-test and multiple regression analysis; p-value<0.05 was considered significant. RESULTS: Gestational age, neonatal birth weight, placental weight, parity, number of fetus and maternal diabetes mellitus were significantly associated with a greater volume of collected umbilical cord blood. Obstetric factors that influenced the total nucleated cell concentration were gestational age, neonatal birth weight, placental weight, number of fetus, and route of delivery. CONCLUSION: To prolong a gestational age as far as possible, at least beyond the 37 completed weeks of gestation, and modifying a method of vaginal delivery or cesarean section rather than conventional vaginal delivery method can increase significantly the volume of collected cord blood and the yield of the concentration of total nucleated cell.