Umbilical cord milking versus delayed cord clamping in term and late-preterm infants: a systematic review and meta-analysis

Abstract

Objective

To conduct a systematic review and meta-analysis to compare the efficacy and safety of umbilical cord milking (UCM) versus delayed cord clamping (DCC) in term and late-preterm infants.

Methods

MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Clinical trial registries, and Gray literature were searched for randomized controlled trials (RCTs) comparing UCM with DCC in term and late-preterm infants for both short-term and long-term outcomes. Intact and cut UCM were compared separately with DCC using subgroup analysis. We used fixed effect model to pool the data. Random effects model was used when there was significant heterogeneity.

Results

Nine studies (1632 infants) were included in the systematic review. Milking was performed on intact cord (i-UCM) in five studies (n = 829) and on cut cord (c-UCM) in four studies (n = 803). Cord milking significantly improved hemoglobin level at 48–72 h of life when compared to DCC (six studies, n = 924, mean difference 0.36 g/dL; 95% CI: 0.19–0.53). In addition, hemoglobin level at six to eight weeks of age was also significantly higher in the studies comparing i-UCM with DCC (two studies, n = 550: mean difference 0.16 g/dL; 95% CI: 0.06–0.27). There was no difference between the UCM group and DCC group for any other outcome. Only one study provided information on growth and hematological parameters at one year of age. Neurodevelopmental outcomes were not reported. None of the studies included non-vigorous infants. The grade of evidence was low to very low for all the outcomes studied.

Conclusion

UCM is comparable to DCC in improving short-term hematological outcomes in term and late-preterm vigorous infants. Trials assessing the effect of UCM on important clinical and long-term outcomes among non-vigorous mature preterm infants are urgently required.

Keywords:

• Umbilical cord milking
• delayed cord clamping
• term infants
• late-preterm infants
• neonates

Acknowledgement

None

Disclosure statement

The authors report no conflict of interest. Dr. Amrit Jeevan drafted the initial manuscript.

Funding source

None

Financial disclosure

The authors have no financial relationships relevant to this article to disclose. None of the authors received any grant for producing the manuscript.

Authors’ contribution

Reviewers AJ, AA, and MB conducted the literature search independently. The studies were assessed for eligibility by reviewers AJ, AA, and MB. AJ drafted the initial manuscript. Reviewers HB, SR, and NK critically reviewed the manuscript. All authors approved the final manuscript.