Effects of cord milking in late preterm infants and full-term infants: A systematic review and meta-analysis

Abstract

Background: Umbilical cord milking (UCM) consists of performing several milkings of the cord from the placenta to the newborn. The objective was to evaluate the effects of UCM on newborns ≥34 weeks’ gestation. Methods: Searches were conducted in MEDLINE, EMBASE, CINAHL, the Cochrane Database of Clinical Trials, and the clinicaltrails.gov database for randomized clinical trials (RCT), with no time or language restrictions, and for articles that compared UCM with other strategies. The main results were initial hemoglobin and hemoglobin after 6 weeks. The data were collected by two reviewers and the quality of the studies was assessed using the Cochrane Manual methodology. Results: The sample included 1845 newborns in 10 RCTs. The use of UCM in ≥34 weeks’ gestation newborns was not related to initial hemoglobin levels (pooled weighted mean difference: (PWMD = 0.40 g/L [−0.16 to 0.95]) or after 6 weeks (PWMD = 0.07 g/L [−0.29 to 0.27]). A reduction in hemoglobin levels was also observed at 6 weeks when the control group had undergone late clamping (PWDM = 0.16g/L [−0.26 to −0.06]). Conclusions: UCM produced no differences in hematologic variables for newborns with ≥34 weeks of gestation relative to controls. However, a slight decrease in hemoglobin levels is observed at 6 weeks when the control group is made up of newborns with late clamping.