Effectiveness and safety of umbilical cord milking in premature infants: A randomized controlled trial

Introduction: Both UCM and DCC are used to treat preterm infants, but there is no uniform standard for the length of UCM. The aim of this work was to explore the effectiveness and safety of different umbilical cord milking (UCM) lengths versus delayed cord clamping (DCC).Methods: We enrolled premature infants from the Affiliated Hospital of Zunyi Medical University between September 2019 and October 2020 with random allocation (1:1:1:1) to the UCM 10 cm, UCM 20 cm, UCM 30 cm, and DCC groups. The primary outcome was hemoglobin at birth.Results: Ultimately, 143 participants completed the trial (UCM 10 cm, n = 35; UCM 20 cm, n = 35; UCM 30 cm, n = 38; DCC, n = 35). The hemoglobin levels were significantly lower at birth in the UCM 10 cm group than in the UCM 20 and 30 cm and DCC groups (182.29 +/- 22.15 vs 202.83 +/- 21.46, 208.82 +/- 20.72, and 198.46 +/- 24.92, P = .001, .001, and .003, respectively). The systolic blood pressure and diastolic pressures in the UCM 30 cm group were higher than those in the UCM 10 and 20 cm and DCC groups at birth, postnatal day 3 and postnatal day 7 (P < .05). The occurrence rates of anemia were significantly higher in the UCM 10 cm group than in the UCM 20 and 30 cm and DCC groups (42.9% vs 14.3%, 10.5%, and 14.3%, all P < .0083). There were no significant differences in heart rate or complications among the 4 groups.Conclusions: A UCM of 20 or 30 cm is a safe, effective operation for preterm infants and could improve blood pressure and hemoglobin levels and reduce anemia.