Milking compared with delayed cord clamping to increase placental transfusion in preterm neonates: a randomized controlled trial. Obstet Gynecol. 2011;117:205-211. [PMID: 21252731 DOI: 10.1097/aog.0b013e3181fe46ff]

Impact of early versus delayed umbilical cord clamping on term neonates' haemoglobin levels: a randomized controlled trial

OBJECTIVE

To compare the effects of early and delayed cord clamping on the haemoglobin levels of neonates delivered at term.

METHODS

This randomized controlled trial enrolled pregnant women during the second stage of labour. They were randomized into either the early cord clamping (ECC) group or the delayed cord clamping (DCC) group in the ratio of 1:1. Following delivery of the baby, the umbilical cords of participants in the ECC group were clamped within 30 s of delivery of the neonate while those of participants in the DCC group were clamped after 2 min from the delivery of the neonate. The primary outcome measure was the effect of ECC and DCC on the haemoglobin levels of neonates delivered at term.

RESULTS

A total of 270 pregnant women were enrolled in the study. Their baseline sociodemographic and clinical characteristics were similar in both groups. There was no significant difference in the mean haemoglobin level between ECC and DCC groups at birth. The mean haemoglobin level of the neonates at 48 h postpartum was significantly higher in the DCC group than the ECC group.

CONCLUSION

DCC at birth was associated with a significant increase in neonatal haemoglobin levels at 48 h postpartum when compared with ECC.Trial Registration: The trial was registered at Pan African Clinical Trial Registry with approval number PACTR202206735622089.

Umbilical cord milking and delayed cord clamping for the prevention of neonatal hypoglycaemia: a systematic review and meta-analysis

BACKGROUND

Placental management strategies such as umbilical cord milking and delayed cord clamping may provide a range of benefits for the newborn. The aim of this review was to assess the effectiveness of umbilical cord milking and delayed cord clamping for the prevention of neonatal hypoglycaemia.

METHODS

Three databases and five clinical trial registries were systematically reviewed to identify randomised controlled trials comparing umbilical cord milking or delayed cord clamping with control in term and preterm infants. The primary outcome was neonatal hypoglycaemia (study defined). Two independent reviewers conducted screening, data extraction and quality assessment. Quality of the included studies was assessed using the Cochrane Risk of Bias tool (RoB-2). Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Meta-analysis using a random effect model was done using Review Manager 5.4. The review was registered prospectively on PROSPERO (CRD42022356553).

RESULTS

Data from 71 studies and 14 268 infants were included in this review; 22 (2 537 infants) compared umbilical cord milking with control, and 50 studies (11 731 infants) compared delayed with early cord clamping. For umbilical cord milking there were no data on neonatal hypoglycaemia, and no differences between groups for any of the secondary outcomes. We found no evidence that delayed cord clamping reduced the incidence of hypoglycaemia (6 studies, 444 infants, RR = 0.87, CI: 0.58 to 1.30, p = 0.49, I2 = 0%). Delayed cord clamping was associated with a 27% reduction in neonatal mortality (15 studies, 3 041 infants, RR = 0.73, CI: 0.55 to 0.98, p = 0.03, I2 = 0%). We found no evidence for the effect of delayed cord clamping for any of the other outcomes. The certainty of evidence was low for all outcomes.

CONCLUSION

We found no data for the effectiveness of umbilical cord milking on neonatal hypoglycaemia, and no evidence that delayed cord clamping reduced the incidence of hypoglycaemia, but the certainty of the evidence was low.

A randomised controlled trial comparing umbilical cord milking to delayed cord clamping at birth in preterm infants 28-36 weeks gestational age

Delayed cord clamping (DCC) is an established practice in perinatology with multiple benefits. However, in instances where the implementation of DCC is not viable, it needs alternatives, especially during caesarean deliveries. A non-inferiority randomized, non-blinded, trial was conducted at a tertiary care referral unit in South India among the preterm newborns (28-36 weeks) randomized to DCC as opposed to intact-umbilical cord milking (UCM). The primary objective was to compare the mean haemoglobin values between the two groups, and the secondary outcome was to compare death and/or major IVH (> Grade II). Of the 132 eligible newborn infants, 99 were randomized to two study groups. Of the 59 and 40 randomised to UCM and DCC, 54 and 36 received the allocated intervention respectively. Preterm infants who underwent UCM had significantly higher haemoglobin (19.97 ± 1.44) as compared to DCC group (18.62 ± 0.98) p-0.0001. The rates of mortality and/or major IVH were comparable between the two groups.

CONCLUSION

UCM may be a feasible alternative to DCC especially in settings where the latter is not achievable, without increasing the risk of adverse effects to the preterm infants, this finding needing further confirmation with larger sample.

TRIAL REGISTRATION

CTRI (Clinical Trial Registry-India) registration number: CTRI/2020/04/024566 (registered prospectively on 13/04/2020).

WHAT IS KNOWN

• Delayed cord clamping (DCC) is recommended as a standard of care for all the stable term and preterm newborn babies at birth.

WHAT IS NEW

• Intact umbilical cord milking may be a reasonable choice of cord management when DCC is unsuccessful, without increasing adverse effects for the new born.

Deferred cord clamping, cord milking, and immediate cord clamping at preterm birth: a systematic review and individual participant data meta-analysis

BACKGROUND

Umbilical cord clamping strategies at preterm birth have the potential to affect important health outcomes. The aim of this study was to compare the effectiveness of deferred cord clamping, umbilical cord milking, and immediate cord clamping in reducing neonatal mortality and morbidity at preterm birth.

METHODS

We conducted a systematic review and individual participant data meta-analysis. We searched medical databases and trial registries (from database inception until Feb 24, 2022; updated June 6, 2023) for randomised controlled trials comparing deferred (also known as delayed) cord clamping, cord milking, and immediate cord clamping for preterm births (<37 weeks' gestation). Quasi-randomised or cluster-randomised trials were excluded. Authors of eligible studies were invited to join the iCOMP collaboration and share individual participant data. All data were checked, harmonised, re-coded, and assessed for risk of bias following prespecified criteria. The primary outcome was death before hospital discharge. We performed intention-to-treat one-stage individual participant data meta-analyses accounting for heterogeneity to examine treatment effects overall and in prespecified subgroup analyses. Certainty of evidence was assessed with Grading of Recommendations Assessment, Development, and Evaluation. This study is registered with PROSPERO, CRD42019136640.

FINDINGS

We identified 2369 records, of which 48 randomised trials provided individual participant data and were eligible for our primary analysis. We included individual participant data on 6367 infants (3303 [55%] male, 2667 [45%] female, two intersex, and 395 missing data). Deferred cord clamping, compared with immediate cord clamping, reduced death before discharge (odds ratio [OR] 0·68 [95% CI 0·51-0·91], high-certainty evidence, 20 studies, n=3260, 232 deaths). For umbilical cord milking compared with immediate cord clamping, no clear evidence was found of a difference in death before discharge (OR 0·73 [0·44-1·20], low certainty, 18 studies, n=1561, 74 deaths). Similarly, for umbilical cord milking compared with deferred cord clamping, no clear evidence was found of a difference in death before discharge (0·95 [0·59-1·53], low certainty, 12 studies, n=1303, 93 deaths). We found no evidence of subgroup differences for the primary outcome, including by gestational age, type of delivery, multiple birth, study year, and perinatal mortality.

INTERPRETATION

This study provides high-certainty evidence that deferred cord clamping, compared with immediate cord clamping, reduces death before discharge in preterm infants. This effect appears to be consistent across several participant-level and trial-level subgroups. These results will inform international treatment recommendations.

FUNDING

Australian National Health and Medical Research Council.

Cut umbilical cord milking (C-UCM) as a mode of placental transfusion in non-vigorous preterm neonates: a randomized controlled trial

Routine practice of delayed cord clamping (DCC) is the standard of care in vigorous neonates. However there is no consensus on the recommended approach to placental transfusion in non-vigorous neonates. In this trial, we tried to examine the effect of cut umbilical cord milking (C-UCM) as compared to early cord clamping (ECC) on hematological and clinical hemodynamic parameters in non-vigorous preterm neonates of 30-35 weeks gestation. The primary outcome assessed was venous hematocrit (Hct) at 48 (± 4) hours of postnatal age. The important secondary outcomes assessed were serum ferritin at 6 weeks of age, mean blood pressure in the initial transitional phase along with important neonatal morbidities and potential complications. In this single centre randomized controlled trial, 134 non vigorous neonates of 30-35 weeks gestation were allocated in a 1:1 ratio to either C-UCM (n = 67) or ECC (n = 67). For statistical analysis, unpaired Student t and Chi square or Fisher's exact test were used. The mean Hct at 48 h was higher in the C-UCM group as compared to the control group, 50.24(4.200) vs 46.16(2.957), p < .0001. Also significantly higher was the mean Hct at 12 h, 6 weeks and mean serum ferritin at 6 weeks of age in the milked group (p < .0001). Mean blood pressure at 1 h and 6 h was also significantly higher in the milked arm. Need for transfusion and inotropes was less in the milked group but not statistically significant. No significant difference in potential complications was observed between the groups.    Conclusion: C-UCM stabilizes initial blood pressure and results in higher hematocrit and improved iron stores. It can be an alternative to DCC in non-vigorous preterm neonates of 30-35 weeks' gestation. Further large multicentric studies are needed to fully establish its efficacy and safety.   Trial registration: CTRI/2021/12/038606; registration date December 14, 2021. What is Known: • DCC is the routinely recommended method of placental transfusion for vigorous neonates but no consensus exist for neonates requiring resuscitation at birth. • C-UCM is easier to perform in non-vigorous neonates but there is paucity of studies in the preterm population. What is New: • C-UCM is effective as well as safe in non-vigorous preterm neonates of 30-35 weeks gestational age. • C-UCM holds promise as an alternative to DCC, especially in resource limited settings and in situations where the later is not feasible.

Optimizing transition: Providing oxygen during intact cord resuscitation

Delayed clamping and cutting of the umbilical cord at birth is standard practice for management for all newborns. Preterm infants may additionally benefit from a combination of ventilation and oxygen provision during intact cord resuscitation. This review highlights both the potential benefits of such a combined approach and the need for further rigorous studies, including randomized controlled trials, of delivery room management in this population.

Cord management in non-vigorous newborns

Cord management in non-vigorous newborns remains up for debate, as limited studies have validated strategies in this high-risk population. While multiple national and international governing bodies now recommend the routine practice of delayed cord clamping (DCC) in vigorous neonates, these organizations have not reached a consensus on the appropriate approach in non-vigorous neonates.1 Benefits of placental transfusion are greatly needed amongst non-vigorous neonates who are at risk of asphyxiation-associated mortality and morbidities, but the need for immediate resuscitation complicates matters. This chapter discusses the physiological benefits of placental transfusion for non-vigorous neonates and reviews the available literature on different umbilical cord management strategies for this population.

Interventions to Reduce Severe Brain Injury Risk in Preterm Neonates: A Systematic Review and Meta-analysis

Importance

Interventions to reduce severe brain injury risk are the prime focus in neonatal clinical trials.

Objective

To evaluate multiple perinatal interventions across clinical settings for reducing the risk of severe intraventricular hemorrhage (sIVH) and cystic periventricular leukomalacia (cPVL) in preterm neonates.

Data Sources

MEDLINE, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases were searched from inception until September 8, 2022, using prespecified search terms and no language restrictions.

Study Selection

Randomized clinical trials (RCTs) that evaluated perinatal interventions, chosen a priori, and reported 1 or more outcomes (sIVH, cPVL, and severe brain injury) were included.

Data Extraction and Synthesis

Two co-authors independently extracted the data, assessed the quality of the trials, and evaluated the certainty of the evidence using the Cochrane GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Fixed-effects pairwise meta-analysis was used for data synthesis.

Main Outcomes and Measures

The 3 prespecified outcomes were sIVH, cPVL, and severe brain injury.

Results

A total of 221 RCTs that assessed 44 perinatal interventions (6 antenatal, 6 delivery room, and 32 neonatal) were included. Meta-analysis showed with moderate certainty that antenatal corticosteroids were associated with small reduction in sIVH risk (risk ratio [RR], 0.54 [95% CI, 0.35-0.82]; absolute risk difference [ARD], -1% [95% CI, -2% to 0%]; number needed to treat [NNT], 80 [95% CI, 48-232]), whereas indomethacin prophylaxis was associated with moderate reduction in sIVH risk (RR, 0.64 [95% CI, 0.52-0.79]; ARD, -5% [95% CI, -8% to -3%]; NNT, 20 [95% CI, 13-39]). Similarly, the meta-analysis showed with low certainty that volume-targeted ventilation was associated with large reduction in risk of sIVH (RR, 0.51 [95% CI, 0.36-0.72]; ARD, -9% [95% CI, -13% to -5%]; NNT, 11 [95% CI, 7-23]). Additionally, early erythropoiesis-stimulating agents (RR, 0.68 [95% CI, 0.57-0.83]; ARD, -3% [95% CI, -4% to -1%]; NNT, 34 [95% CI, 22-67]) and prophylactic ethamsylate (RR, 0.68 [95% CI, 0.48-0.97]; ARD, -4% [95% CI, -7% to 0%]; NNT, 26 [95% CI, 13-372]) were associated with moderate reduction in sIVH risk (low certainty). The meta-analysis also showed with low certainty that compared with delayed cord clamping, umbilical cord milking was associated with a moderate increase in sIVH risk (RR, 1.82 [95% CI, 1.03-3.21]; ARD, 3% [95% CI, 0%-6%]; NNT, -30 [95% CI, -368 to -16]).

Conclusions and Relevance

Results of this study suggest that a few interventions, including antenatal corticosteroids and indomethacin prophylaxis, were associated with reduction in sIVH risk (moderate certainty), and volume-targeted ventilation, early erythropoiesis-stimulating agents, and prophylactic ethamsylate were associated with reduction in sIVH risk (low certainty) in preterm neonates. However, clinicians should carefully consider all of the critical factors that may affect applicability in these interventions, including certainty of the evidence, before applying them to clinical practice.

Premature infants receiving delayed cord clamping with and without cord milking: a randomized control trial

BACKGROUND

Preterm infants often have long hospital stays and frequent blood tests; they often develop anemia requiring multiple blood transfusions. Placental transfusion via delayed cord clamping (DCC) or umbilical cord milking (UCM) helps increase blood volume. We hypothesized umbilical cord milking (UCM), together with DCC, would be superior in reducing blood transfusions.

OBJECTIVES

To compare the effects of DCC and DCC combined with UCM on hematologic outcomes among preterm infants.

METHODS

One hundred twenty singleton preterm infants born at 280/7- 336/7 weeks of gestation at Thammasat University Hospital were enrolled in an open-label, randomized, controlled trial. They were placed into three groups (1:1:1) by a block-of-three randomization: DCC for 45 s, DCC with UCM performed before clamping (DCM-B), and DCC with UCM performed after clamping (DCM-A). The primary outcomes were hematocrit levels and number of infants receiving blood transfusions during the first 28 days of life. Intraventricular hemorrhage (IVH) and necrotizing enterocolitis (NEC) were secondary outcomes. Analyses were performed with an intent-to-treat approach.

RESULTS

One hundred twenty preterm infants were randomized. There was no statistically significant difference in neonatal outcomes; hematocrit on admission 54.0 ± 5.5, 53.3 ± 6.0, and 54.3 ± 5.8 (p = 0.88), receiving blood transfusions 25%, 20%, and 12.5% (p = 0.24), incidence of NEC 7.5, 0 and 10% (p = 0.78) in the DCC, DCM-B and DCM-A groups, respectively. There were no preterm infants with severe IVH, polycythemia, maternal or neonatal death.

CONCLUSION

The placental transfusion techniques utilized, DCC and DCC combined with UCM, provided the same benefits for preterm infants born at GA 28 and 33 weeks in terms of reducing the need for RBC transfusions, severities of IVH and incidence of NEC without increasing comorbidity.

TRIAL REGISTRATION

TCTR20190131002 . Registered 31 January 2019-Retrospectively registered.

Umbilical cord milking-benefits and risks

The most common methods for providing additional placental blood to a newborn are delayed cord clamping (DCC) and umbilical cord milking (UCM). However, DCC carries the potential risk of hypothermia due to extended exposure to the cold environment in the operating room or delivery room, as well as a delay in performing resuscitation. As an alternative, umbilical cord milking (UCM) and delayed cord clamping with resuscitation (DCC-R) have been studied, as they allow for immediate resuscitation after birth. Given the relative ease of performing UCM compared to DCC-R, UCM is being strongly considered as a practical option in non-vigorous term and near-term neonates, as well as preterm neonates requiring immediate respiratory support. However, the safety profile of UCM, particularly in premature newborns, remains a concern. This review will highlight the currently known benefits and risks of umbilical cord milking and explore ongoing studies.

A newborn's "life line" - A review of umbilical cord management strategies

Literature supporting various umbilical management strategies have increased substantially over the past decade. Delayed cord clamping and umbilical cord milking are increasing embraced by obstetricians and neonatologists, and multiple international governing bodies now endorse these practices. This review summarizes the benefits and limitations of the different umbilical cord management strategies for term, near-term, and preterm neonates. Additional studies are underway to elucidate the safety profile of these practices, long term outcomes, and variations within these strategies that could potentially augment the benefits.

The hematological impact of umbilical cord milking versus delayed cord clamping in premature neonates: a randomized controlled trial

BACKGROUND

The hematological impact of umbilical cord milking (UCM) was compared to that of delayed cord clamping (DCC) as a faster placental transfusion technique for preterm neonates (between 24 and 34 + 6 weeks gestation). A comparison of important neonatal morbidities was also made.

METHODS

This was an open-label randomized trial conducted from June 8, 2017, to April 22, 2019. Two hundred patients with preterm deliveries (24 and 34 + 6 weeks gestation) were assigned to the DCC or UCM group at random at a ratio of 1:1. The study power was 80% for a difference in the hematocrit value of 3% and Hb value of one gram, and an alpha error of 0.05.

RESULTS

The following variables were analyzed in the comparison of UCM vs. DCC: first draw hemoglobin: 17.0 ± 1.9 vs. 16.8 ± 1.8 gm/dl (95% CI -0.75-0.29, P 0.383); first draw hematocrit: 55.6 ± 6.4 vs. 55.2 ± 6.4% (95% CI -2.18-1.38, P 0.659); peak hematocrit: 56.9 ± 6.4 vs. 56.3 ± 6.7% (95% CI -2.41-1.26, P 0.537); the need for respiratory assistance (47% vs. 30%, P 0.020), inotropes (16% vs. 6%, P 0.040), and blood transfusion (26% vs. 12%, P 0.018); and the occurrence of intraventricular hemorrhage (9% vs. 5%, P 0.407), necrotizing enterocolitis (6% vs. 2%, P 0.279), sepsis (25% vs. 15%, P 0.111), and neonatal death (13% vs. 4%, P 0.40).

CONCLUSION

UCM facilitated a rapid transfer of placental blood equivalent to that of DCC for premature neonates. However, it resulted in increased rates of interventions and morbidities, especially in extremely preterm neonates.

TRIAL REGISTRATION

The clinical trial was registered on May 10, 2017, with registration number (NCT03147846).

Umbilical Cord Management in Late Preterm and Term Infants: A Randomized Controlled Trial

OBJECTIVE

The study aimed to compare the effects of three different methods of umbilical cord management on hematological parameters in term and late-preterm infants.

STUDY DESIGN

A randomized controlled trial comparing intact-umbilical cord milking (I-UCM) with cut-umbilical cord milking (C-UCM) and immediate cord clamping (ICC) in neonates born >35 weeks' gestation.

RESULTS

A total of 587 infants were evaluated. Of these, 197 were assigned to I-UCM, 190 to C-UCM, and 200 to ICC. Mean hemoglobin and hematocrit levels at 48 hours of age were higher in I-UCM group compared with the ICC group (p = 0.002 and p = 0.010, respectively).

CONCLUSION

These findings suggest that I-UCM is more beneficial choice. Further trials are needed to assess the various long- and short-term effects of different cord milking methods.

KEY POINTS

· This is the first study comparing these three methods (I-UCM, C-UCM, and ICC) concurrently.. · I-UCM is more beneficial choice.. · Although the terms I-UCM and C-UCM are often used interchangeably, these are different procedures..

Cardiopulmonary Resuscitation with an Intact Umbilical Cord

The body of literature supporting different umbilical management strategies has increased over the past decade as the role of cord management in neonatal transition is realized. Multiple international governing bodies endorse delayed cord clamping, and this practice is now widely accepted by obstetricians and neonatologists. Although term and preterm neonates benefit in some ways from delayed cord clamping, additional research on variations in this practice, including resuscitation with an intact cord, aim to find the optimal cord management practice that reduces mortality and major morbidities.

[Influence of umbilical cord milking versus delayed cord clamping on the early prognosis of preterm infants with a gestational age of <34 weeks: a Meta analysis]

OBJECTIVES

To study the influence of umbilical cord milking versus delayed cord clamping on the early prognosis of preterm infants with a gestational age of <34 weeks.

METHODS

PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, China National Knowledge Infrastructure, Wanfang Data, Weipu Database, and SinoMed were searched for randomized controlled trials on umbilical cord milking versus delayed cord clamping in preterm infants with a gestational age of <34 weeks published up to November 2021. According to the inclusion and exclusion criteria, two researchers independently performed literature screening, quality evaluation, and data extraction. Review Manger 5.4 was used for Meta analysis.

RESULTS

A total of 11 articles were included in the analysis, with 1 621 preterm infants in total, among whom there were 809 infants in the umbilical cord milking group and 812 in the delayed cord clamping group. The Meta analysis showed that compared with delayed cord clamping, umbilical cord milking increased the mean blood pressure after birth (weighted mean difference=3.61, 95%CI: 0.73-6.50, P=0.01), but it also increased the incidence rate of severe intraventricular hemorrhage (RR=1.83, 95%CI: 1.08-3.09, P=0.02). There were no significant differences between the two groups in hemoglobin, hematocrit, blood transfusion rate, proportion of infants undergoing phototherapy, bilirubin peak, and incidence rates of complications such as periventricular leukomalacia and necrotizing enterocolitis (P>0.05).

CONCLUSIONS

Compared with delayed cord clamping, umbilical cord milking may increase the risk of severe intraventricular hemorrhage in preterm infants with a gestational age of <34 weeks; however, more high-quality large-sample randomized controlled trials are needed for further confirmation.

What does the evidence tell us? Revisiting optimal cord management at the time of birth

A newborn who receives a placental transfusion at birth from delayed cord clamping (DCC) obtains about 30% more blood volume than those with immediate cord clamping (ICC). Benefits for term neonates include higher hemoglobin levels, less iron deficiency in infancy, improved myelination out to 12 months, and better motor and social development at 4 years of age especially in boys. For preterm infants, benefits include less intraventricular hemorrhage, fewer gastrointestinal issues, lower transfusion requirements, and less mortality in the neonatal intensive care unit by 30%. Ventilation before clamping the umbilical cord can reduce large swings in cardiovascular function and help to stabilize the neonate. Hypovolemia, often associated with nuchal cord or shoulder dystocia, may lead to an inflammatory cascade and subsequent ischemic injury. A sudden unexpected neonatal asystole at birth may occur from severe hypovolemia. The restoration of blood volume is an important action to protect the hearts and brains of neonates. Currently, protocols for resuscitation call for ICC. However, receiving an adequate blood volume via placental transfusion may be protective for distressed neonates as it prevents hypovolemia and supports optimal perfusion to all organs. Bringing the resuscitation to the mother's bedside is a novel concept and supports an intact umbilical cord. When one cannot wait, cord milking several times can be done quickly within the resuscitation guidelines. Cord blood gases can be collected with optimal cord management.   Conclusion: Adopting a policy for resuscitation with an intact cord in a hospital setting takes a coordinated effort and requires teamwork by obstetrics, pediatrics, midwifery, and nursing.

Effects of spontaneous first breath on placental transfusion in term neonates born by cesarean section: A randomized controlled trial

BACKGROUND

The role of umbilical cord management in placental transfusion in cesarean section (CS) requires clarification. The spontaneous first breath may be more important than the timing of cord clamping for placental transfusion in neonates born by CS.

OBJECTIVE

This study aimed to evaluate the impact of cord clamping after the first spontaneous breath on placental transfusion in neonates born by CS.

METHODS

We recruited women with a live singleton pregnancy at ≥37.0 weeks of gestation admitted for CS. The interventions performed, such as physiologic-based cord clamping (PBCC), intact-umbilical cord milking (I-UCM), 30-s delay in cord clamping (30-s DCC), and 60-s delay in cord clamping (60-s DCC), were noted and placed in a sealed envelope. The sealed envelope was opened immediately before delivery to perform randomization.

RESULTS

A total of 123 infants were eligible for evaluation. Of these, 31, 30, 32, and 30 were assigned to the PBCC, I-UCM, 30-s DCC, and 60-s DCC groups, respectively. The mean hemoglobin (Hb) and mean hematocrit (Hct) were significantly higher in the 60-s DCC group than in the PBCC group (p = 0.028 and 0.019, respectively), but no difference was noted among the I-UCM, 30-s DCC, and PBCC groups at 36 h of age. Further, no significant differences were observed in the mean Hb and mean Hct among the I-UCM, 60-s DCC, and 30-s DCC groups. Peak total serum bilirubin (TSB) levels were higher in the 60-s DCC group than in the I-UCM and PBCC groups (p = 0.017), but there was no difference between the 60-s DCC and 30-s DCC groups during the first week of life. The phototherapy requirement was higher in 60-s DCC than in IUCM and 30-sDCC (p = 0.001).

CONCLUSIONS

Our findings demonstrated that PBCC, 30-s DCC, and I-UCM in neonates born by CS had no significant differences from each other on placental transfusion. The Hb and Hct in the neonates were higher after 60-s DCC than after PBCC.

Effects of Umbilical Cord Milking on Anemia in Preterm Infants: A Multicenter Randomized Controlled Trial

OBJECTIVE

This study aimed to investigate whether umbilical cord milking (UCM) prevents and controls anemia in preterm infants, as compared with immediate cord clamping (ICC).

STUDY DESIGN

Pregnant women delivering at <34 weeks' gestation in four hospitals were randomly assigned to undergo UCM or ICC from July 2017 to June 2019. Hematological parameters and iron status were collected and analyzed as primary outcomes at 24 hours, 1 week, 2 weeks, and 6 months after delivery.

RESULTS

Neonates receiving UCM had significant higher levels of hemoglobin (Hb), hematocrit, and serum iron (p < 0.05). Lower prevalence of anemia and lower need for transfusions were noted in UCM group. Although UCM was associated with prolonged duration of phototherapy, the maximum levels of bilirubin were similar between two groups (p > 0.05).

CONCLUSION

UCM is an effective intervention to help preterm infants experience less anemia with the potential to increase blood volume, as seen by higher Hb levels and more enhanced iron stores.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Neonatal Life Support; Education, Implementation, and Teams; First Aid Task Forces; and the COVID-19 Working Group

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

Delayed cord clamping: Time for physiologic implementation

Delayed cord clamping has been shown to be beneficial in both preterm and term babies. Practice guidelines have not been consistent between centers and the practice of delayed cord clamping has not been standardized. The concept of physiologic-based cord clamping emerged into practice as well. Cord milking has different physiological effect and might be harmful in preterm babies.

Differential Alveolar and Systemic Oxygenation during Preterm Resuscitation with 100% Oxygen during Delayed Cord Clamping

OBJECTIVE

 Delayed cord clamping (DCC) and 21 to 30% O₂ resuscitation is recommended for preterm infants but is commonly associated with low pulmonary blood flow (Qp) and hypoxia. 100% O₂ supplementation during DCC for 60 seconds followed by 30% O₂ may increase Qp and oxygen saturation (SpO₂).

STUDY DESIGN

 Preterm lambs (125-127 days of gestation) were resuscitated with 100% O₂ with immediate cord clamping (ICC, n = 7) or ICC + 30% O₂, and titrated to target SpO₂ (n = 7) or DCC + 100% O₂ for 60 seconds, which followed by cord clamping and 30% O₂ titration (n = 7). Seven preterm (23-27 weeks of gestation) human infants received continuous positive airway pressure (CPAP) + 100% O₂ for 60 seconds during DCC, cord clamping, and 30% O₂ supplementation after cord clamping.

RESULTS

 Preterm lambs in the ICC + 100% O₂ group resulted in PaO₂ (77 ± 25 mmHg), SpO₂ (77 ± 11%), and Qp (27 ± 9 mL/kg/min) at 60 seconds. ICC + 30% O₂ led to low Qp (14 ± 3 mL/kg/min), low SpO₂ (43 ± 26%), and PaO₂ (19 ± 7 mmHg). DCC + 100% O₂ led to similar Qp (28 ± 6 mL/kg/min) as ICC + 100% O₂ with lower PaO₂. In human infants, DCC + CPAP with 100% O₂ for 60 seconds, which followed by weaning to 30% resulted in SpO₂ of 92 ± 11% with all infants >80% at 5 minutes with 100% survival without severe intraventricular hemorrhage.

CONCLUSION

 DCC + 100% O₂ for 60 seconds increased Qp probably due to transient alveolar hyperoxia with systemic normoxia due to "dilution" by umbilical venous return. Larger translational and clinical studies are warranted to confirm these findings.

KEY POINTS

· Transient alveolar hyperoxia during delayed cord clamping can enhance pulmonary vasodilation.. · Placental transfusion buffers systemic oxygen tension and limits hyperoxia.. · Use of 100% oxygen for 60 seconds during DCC was associated with SpO2 ≥80% by 5 minutes..

Umbilical Cord Milking vs Delayed Cord Clamping and Associations with In-Hospital Outcomes among Extremely Premature Infants

OBJECTIVE

To compare in-hospital outcomes after umbilical cord milking vs delayed cord clamping among infants <29 weeks of gestation.

STUDY DESIGN

Multicenter retrospective study of infants born <29 weeks of gestation from 2016 to 2018 without congenital anomalies who received active treatment at delivery and were exposed to umbilical cord milking or delayed cord clamping. The primary outcome was mortality or severe (grade III or IV) intraventricular hemorrhage (IVH) by 36 weeks of postmenstrual age (PMA). Secondary outcomes assessed at 36 weeks of PMA were mortality, severe IVH, any IVH or mortality, and a composite of mortality or major morbidity. Outcomes were assessed using multivariable regression, incorporating mortality risk factors identified a priori, confounders, and center. A prespecified, exploratory analysis evaluated severe IVH in 2 gestational age strata, 22-24^6/7 and 25-28^6/7 weeks.

RESULTS

Among 1834 infants, 23.6% were exposed to umbilical cord milking and 76.4% to delayed cord clamping. The primary outcome, mortality or severe IVH, occurred in 21.1% of infants: 28.3% exposed to umbilical cord milking and 19.1% exposed to delayed cord clamping, with an aOR that was similar between groups (aOR 1.45, 95% CI 0.93, 2.26). Infants exposed to umbilical cord milking had higher odds of severe IVH (19.8% umbilical cord milking vs 11.8% delayed cord clamping, aOR 1.70 95% CI 1.20, 2.43), as did the 25-28^6/7 week stratum (14.8% umbilical cord milking vs 7.4% delayed cord clamping, aOR 1.89 95% CI 1.22, 2.95). Other secondary outcomes were similar between groups.

CONCLUSIONS

This analysis of extremely preterm infants suggests that delayed cord clamping is the preferred practice for placental transfusion, as umbilical cord milking exposure was associated with an increase in the adverse outcome of severe IVH.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00063063.

Association of Umbilical Cord Management Strategies With Outcomes of Preterm Infants: A Systematic Review and Network Meta-analysis

IMPORTANCE

It is unclear which umbilical cord management strategy is the best for preventing mortality and morbidities in preterm infants.

OBJECTIVE

To systematically review and conduct a network meta-analysis comparing 4 umbilical cord management strategies for preterm infants: immediate umbilical cord clamping (ICC), delayed umbilical cord clamping (DCC), umbilical cord milking (UCM), and UCM and DCC.

DATA SOURCES

PubMed, Embase, CINAHL, and Cochrane CENTRAL databases were searched from inception until September 11, 2020.

STUDY SELECTION

Randomized clinical trials comparing different umbilical cord management strategies for preterm infants were included.

DATA EXTRACTION AND SYNTHESIS

Data were extracted for bayesian random-effects meta-analysis to estimate the relative treatment effects (odds ratios [OR] and 95% credible intervals [CrI]) and surface under the cumulative ranking curve values.

MAIN OUTCOMES AND MEASURES

The primary outcome was predischarge mortality. The secondary outcomes were intraventricular hemorrhage, severe intraventricular hemorrhage, need for packed red blood cell transfusion, and other neonatal morbidities. Confidence in network meta-analysis software was used to assess the quality of evidence and grade outcomes.

RESULTS

Fifty-six studies enrolled 6852 preterm infants. Compared with ICC, DCC was associated with lower odds of mortality (22 trials, 3083 participants; 7.6% vs 5.0%; OR, 0.64; 95% CrI, 0.39-0.99), intraventricular hemorrhage (25 trials, 3316 participants; 17.8% vs 15.4%; OR, 0.73; 95% CrI, 0.54-0.97), and need for packed red blood cell transfusion (18 trials, 2904 participants; 46.9% vs 38.3%; OR, 0.48; 95% CrI, 0.32-0.66). Compared with ICC, UCM was associated with lower odds of intraventricular hemorrhage (10 trials, 645 participants; 22.5% vs 16.2%; OR, 0.58; 95% CrI, 0.38-0.84) and need for packed red blood cell transfusion (9 trials, 688 participants; 47.3% vs 32.3%; OR, 0.36; 95% CrI, 0.23-0.53), with no significant differences for other secondary outcomes. There was no significant difference between UCM and DCC for any outcome.

CONCLUSIONS AND RELEVANCE

Compared with ICC, DCC was associated with the lower odds of mortality in preterm infants. Compared with ICC, DCC and UCM were associated with reductions in intraventricular hemorrhage and need for packed red cell transfusion. There was no significant difference between UCM and DCC for any outcome. Further studies directly comparing DCC and UCM are needed.

A 3-armed multicenter randomized controlled trial: Placental Transfusion in Very Preterm Infants (PT-VPI)

Preterm infants constitute an important proportion of neonatal deaths and various complications, and very preterm infants (VPI) are more likely to develop severe complications, such as intraventricular hemorrhage (IVH), anemia, and sepsis. It has been confirmed that placental transfusion can supplement blood volume in infants and reduce preterm-associated complications, which is further conducive to the development of the nervous system and a better long-term prognosis. Based on these advantages, placental transfusion has been widely used in VPI. There are three main types of placental transfusion: delayed cord clamping (DCC), intact umbilical cord milking (I-UCM), and cut umbilical cord milking (C-UCM). However, the optimal method for PT-VPI remains controversial, and it is urgent to identify the best method of placental transfusion. We plan to fully evaluate the safety and effectiveness of these three placental transfusion methods in VPI in a 3-arm multicenter randomized controlled trial: Placental Transfusion in Very Preterm Infants (PT-VPI). Trial registration: chictr.org.cn, number ChiCTR2000030953.

Umbilical Cord Management for Newborns <34 Weeks' Gestation: A Meta-analysis

CONTEXT

The International Liaison Committee on Resuscitation prioritized scientific review of umbilical cord management strategies at preterm birth.

OBJECTIVE

To determine the effects of umbilical cord management strategies (including timing of cord clamping and cord milking) in preterm infants <34 weeks' gestation.

DATA SOURCES

Cochrane Central Register of Controlled Trials, Medline, PubMed, Embase, CINAHL, and trial registries were searched through July 2019 for randomized controlled trials assessing timing of cord clamping and/or cord milking.

STUDY SELECTION

Two authors independently assessed trial eligibility, extracted data, appraised risk of bias, and assessed evidence certainty (GRADE).

DATA EXTRACTION

We identified 42 randomized controlled trials (including 5772 infants) investigating 4 different comparisons of cord management interventions.

RESULTS

Compared to early cord clamping, delayed cord clamping (DCC) and intact-cord milking (ICM) may slightly improve survival; however, both are compatible with no effect (DCC: risk ratio: 1.02, 95% confidence interval: 1.00 to 1.04, n = 2988 infants, moderate certainty evidence; ICM: risk ratio: 1.02, 95% confidence interval: 0.98 to 1.06, n = 945 infants, moderate certainty evidence). DCC and ICM both probably improve hematologic measures but may not affect major neonatal morbidities.

LIMITATIONS

For many of the included comparisons and outcomes, certainty of evidence was low. Our subgroup analyses were limited by few researchers reporting subgroup data.

CONCLUSIONS

DCC appears to be associated with some benefit for infants born <34 weeks. Cord milking needs further evidence to determine potential benefits or harms. The ideal cord management strategy for preterm infants is still unknown, but early clamping may be harmful.

A Randomized Controlled Trial of Intact Cord Milking versus Immediate Cord Clamping in Term Infants Born by Elective Cesarean Section

OBJECTIVE

We evaluated whether intact umbilical cord milking (UCM) is more effective than immediate cord clamping (ICC) in enhancing placental transfusion after elective cesarean delivery.

STUDY DESIGN

In a randomized trial, volume of placental transfusion was assessed by Δ hematocrit (Hct) between neonatal cord blood and capillary heel blood at 48 hours of age, corrected for the change in body weight.

RESULTS

There were no significant differences in cord blood mean Hct values at birth (UCM, 44.5 ± 4.8 vs. ICC, 44.9 ± 4.2%, p = 0.74). Conversely, at 48 hours of age, the UCM group had significantly higher capillary heel Hct values (UCM, 53.7 ± 5.9 vs. ICC, 49.8 ± 4.6%, p < 0.001), supporting a higher placental transfusion volume (Δ Hct, UCM 9.2 ± 5.2 vs. ICC 4.8 ± 4.7, p < 0.001), despite comparable neonatal body weight decrease (UCM, -7.3 vs. ICC, -6.8%, p = 0.77).

CONCLUSION

Higher Δ Hct between cord blood at birth and capillary heel blood at 48 hours of age, corrected for the change in body weight, suggests that intact UCM is an efficacious and safe procedure to enhance placental transfusion among neonates born via elective cesarean delivery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT03668782.

Effect of umbilical cord milking versus delayed cord clamping on preterm neonates in Kenya: A randomized controlled trial

Background

Delayed cord clamping (DCC) is a placental to new-born transfusion strategy recommended by obstetric and gynaecological societies. Though not widely adopted, umbilical cord milking (UCM) may achieve faster transfusion when DCC cannot be performed such as when a neonate requires resuscitation.

Methods

Pragmatic, two-arm, randomized clinical trial in which consenting women in spontaneous labour or provider-initiated delivery at 28 to less than 37 weeks at Kenyatta National Hospital in Nairobi, Kenya, were enrolled. At delivery, stable preterm infants were randomized to UCM (4 times) or DCC (60 seconds). Neonatal samples were collected for analysis at 24 hours after delivery. Maternal primary PPH (within 24 hours) and neonatal jaundice (within 1 week) were evaluated clinically. The primary outcome was the mean neonatal haemoglobin level at 24 hours after birth. Modified Intention to treat analysis was used for all outcomes. P-value was significant at p<0.05.

Results

Between March 2018 to March 2019, 344 pregnant women underwent screening, and 280 eligible participants were randomized when delivery was imminent. The intervention was not performed on 19 ineligible neonates. Of the remaining 260 neonates, 133 underwent UCM while 128 underwent DCC. Maternal and neonatal baseline characteristics were similar. The mean neonatal haemoglobin (17.1 vs 17.5 grams per decilitre, p = 0.191), haematocrit (49.6% vs 50.3%, p = 0.362), anaemia (9.8% vs 11.7%, p = 0.627), maternal PPH (2.3% vs 3.1%, p = 0.719) were similar between UCM and DCC respectfully. However, neonatal polycythaemia (2.3% vs 8.6%, p = 0.024) and neonatal jaundice (6.8% vs 15.6%, p = 0.024) were statistically significantly lower in UCM compared to DCC.

Conclusion

UCM compared to DCC for preterm neonates resulted in similar outcomes for neonatal haemoglobin, haematocrit, anaemia and maternal primary PPH and a lower proportion of neonatal polycythaemia and clinical jaundice. UCM offers a comparable method of placental transfusion compared to DCC and may be considered as an alternative to DCC in preterm neonates at 28 to <37 weeks’ gestation.

Prevention of iron deficiency anemia in infants and toddlers

Anemia, defined as a low blood hemoglobin concentration, is a major global public health problem. Identification of anemia is crucial to public health interventions. It is estimated globally that 273 million children under 5 years of age were anemic in 2011, and about ~50% of those cases were attributable to iron deficiency (Lancet Global Health 1:e16-e25, 2013). Iron-deficiency anemia (IDA) in infants adversely impacts short-term hematological indices and long-term neuro-cognitive functions of learning and memory that result in both fatigue and low economic productivity. IDA contributes to death and disability and is an important risk factor for maternal and perinatal mortality, including the risks for stillbirths, prematurity, and low birth weight (Comparative Quantification of Health Risks: Global and Regional Burden of Disease Attributable to Selected Major Risk Factors. Ch. 3 (World Health Organization, Geneva, 2004)). Reduction in early infantile anemia and newborn mortality rates is possible with easily implemented, low- to no-cost intervention such as delayed cord clamping (DCC). DCC until 1-3 min after birth facilitates placental transfusion and iron-rich blood flow to the newborn. DCC, an effective anemia prevention strategy, requires cooperation among health providers involved in childbirth, and a participatory culture change in public health. Public intervention strategies must consider multiple factors associated with anemia listed in this review before designing intervention studies that aim to reduce anemia prevalence in infants and toddlers. IMPACT: Anemia, defined as a low blood hemoglobin concentration, is a major global public health problem and identification of anemia is crucial to public health interventions. Delayed cord clamping (DCC) until 1-3 min after birth facilitates placental transfusion and iron-rich blood flow to the newborn. Reduction in early infantile anemia and newborn mortality rates is possible with easily implemented, low- to no-cost intervention such as DCC.

Antenatal and perinatal factors influencing neonatal blood pressure: a systematic review

OBJECTIVE

A comprehensive understanding of the factors contributing to perinatal blood pressure is vital to ensure optimal postnatal hemodynamic support. The objective of this study was to review existing literature on maternal and perinatal factors influencing blood pressure in neonates up to 3 months corrected age.

METHODS

A systematic search of published literature in OVID Medline, OVID Embase and the COCHRANE library identified publications relating to maternal factors affecting blood pressure of neonates up to corrected age of 3 months. Summary data were extracted and compared (PROSPERO CRD42018092886).

RESULTS

Of the 3683 non-duplicate publications identified, 44 were eligible for inclusion in this review. Topics elicited were sociodemographic factors, maternal health status, medications, smoking during pregnancy, and cord management at birth. Limited data were available for each factor. Results regarding the impact of these factors on neonatal blood pressure were inconsistent across studies.

CONCLUSIONS

There is insufficient evidence to draw definitive conclusions regarding the impact of various maternal and perinatal factors on neonatal blood pressure. Future investigations of neonatal cardiovascular therapies should account for these factors in their study design. Similarly, studies on maternal diseases and perinatal interventions should include neonatal blood pressure as part of their primary or secondary analyses.

Short-term efficacy of umbilical cord milking in preterm infants: systematic review and meta-analysis

BACKGROUND

To systematically evaluate short-term efficacy of UCM versus other interventions in preterm infants.

METHODS

Six engines were searched until February 2020 for randomized controlled trials (RCTs) assessing UCM versus immediate cord clamping (ICC), delayed cord clamping (DCC), or no intervention. Primary outcomes were overall mortality, intraventricular hemorrhage (IVH), and patent ductus arteriosus (PDA); secondary outcomes were need for blood transfusion, mean blood pressure (MBP), serum hemoglobin (Hb), and ferritin levels. Random-effects meta-analyses were used.

RESULTS

Fourteen RCTs (n = 1708) were included. In comparison to ICC, UCM did not decrease mortality (RR 0.5, 95% CI 0.2-1.1), IVH (RR 0.7, 95% CI 0.5-1.0), or PDA (RR 1.0, 95% CI 0.7-1.5). However, UCM reduced need of blood transfusion (RR 0.5, 95% CI 0.3-0.9) and increased MBP (MD 2.5 mm Hg, 95% CI 0.5-4.5), Hb (MD 1.2 g/dL, 95% CI 0.8-1.6), and ferritin (MD 151.4 ng/dL, 95% CI 59.5-243.3). In comparison to DCC, UCM did not reduce mortality, IVH, PDA, or need of blood transfusion but increased MBP (MD 3.7, 95% CI 0.6-6.9) and Hb (MD 0.3, 95% CI -0.2-0.8). Only two RCTs had high risk of bias.

CONCLUSIONS

UCM did not decrease short-term clinical outcomes in comparison to ICC or DCC in preterm infants. Intermediate outcomes improved significantly with UCM.

IMPACT

In 14 randomized controlled trials (RCTs), umbilical cord milking (UCM) did not reduce mortality, intraventricular hemorrhage, or patent ductus arteriosus compared to immediate (ICC) or delayed cord clamping (DCC). UCM improved mean blood pressure and hemoglobin levels compared to ICC or DCC. In comparison to ICC, UCM reduced the need for blood transfusion. We updated searches until February 2020, stratified by type of control, and performed subgroup analyses. There was low quality of evidence about clinical efficacy of UCM. Most of RCTs had low risk of bias. UCM cannot be recommended as standard of care for preterm infants.

Umbilical cord milking in preterm infants: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of the efficacy and safety of umbilical cord milking in preterm infants.

DESIGN

Randomised controlled trials comparing umbilical cord milking with delayed cord clamping/immediate cord clamping in preterm infants were identified by searching databases, clinical trial registries and reference list of relevant studies in November 2019. Fixed effects model was used to pool the data on various clinically relevant outcomes.

MAIN OUTCOME MEASURES

Mortality and morbidities in preterm neonates.

RESULTS

Nineteen studies (2014 preterm infants) were included. Five studies (n=922) compared cord milking with delayed cord clamping, whereas 14 studies (n=1092) compared milking with immediate cord clamping. Cord milking, as opposed to delayed cord clamping, significantly increased the risk of intraventricular haemorrhage (grade III or more) (risk ratio (RR): 1.95 (95% CI 1.01 to 3.76), p=0.05). When compared with immediate cord clamping, cord milking reduced the need for packed RBC transfusions (RR:0.56 (95% CI 0.43 to 0.73), p<0.001). There was limited information on long-term neurodevelopmental outcomes. The grade of evidence was moderate or low for the various outcomes analysed.

CONCLUSION

Umbilical cord milking, when compared with delayed cord clamping, significantly increased the risk of severe intraventricular haemorrhage in preterm infants, especially at lower gestational ages. Cord milking, when compared with immediate cord clamping, reduced the need for packed RBC transfusions but did not improve clinical outcomes. Hence, cord milking cannot be considered as placental transfusion strategy in preterm infants based on the currently available evidence.

A Comparison of Strategies for Managing the Umbilical Cord at Birth in Preterm Infants

OBJECTIVE

To evaluate the rates of practice, and the associations between different cord management strategies at birth (delayed cord clamping [DCC], umbilical cord milking [UCM], and early cord clamping [ECC]) and mortality or major morbidity, rates of blood transfusion, and peak serum bilirubin in a large national cohort of very preterm infants.

STUDY DESIGN

We retrospectively studied preterm infants <33 weeks of gestation admitted to the Canadian Neonatal Network between January 2015 and December 2017. Patients who received ECC (<30 seconds), UCM, or DCC (≥30 seconds) were compared. Multiple generalized linear/quantile logistic regression models were used.

RESULTS

Of 12 749 admitted infants, 9729 were included; 4916 (50.5%) received ECC, 394 (4.1%) UCM, and 4419 (45.4%) DCC. After adjustment for potential confounders identified between groups in univariate analyses, the odds of mortality or major morbidity were higher in the ECC group when compared with UCM group (aOR, 1.18; 95% CI, 1.03-1.35). Mortality and intraventricular hemorrhage were associated with ECC as compared with DCC (aOR, 1.6 [95% CI, 1.22-2.1] and aOR, 1.29 [95% CI, 1.19-1.41], respectively). The odds of severe intraventricular hemorrhage were higher with UCM compared with DCC (aOR, 1.38; 95% CI, 1.05-1.81). Rates of blood transfusion were higher with ECC compared with UCM and DCC (aOR, 1.67 [95% CI, 1.31-2.14] and aOR, 1.68 [95% CI, 1.35-2.09], respectively), although peak serum bilirubin levels were not significantly different.

CONCLUSIONS

Both DCC and UCM were associated with better short-term outcomes than ECC; however, the odds of severe intraventricular hemorrhage were higher with UCM compared with DCC.

Umbilical cord management strategies at cesarean section

AIM

To evaluate the effect of different strategies to improve placental transfusion in cesarean section (CS).

METHODS

Retrospective analysis of all singleton term pregnancies that underwent CS over 6 months. Delayed umbilical cord clamping (dUCC) was defined as one done at least 60 s after birth. Umbilical cord milking (UCM) was an option when waiting 60 s was deemed unsafe. The two strategies were compared against early (<60 s) umbilical cord clamping (eUCC) without milking. Neonatal hematocrit (Hct) at 48 h was the main outcome variable.

RESULTS

Of the 223 CS in the cohort, 100 were performed in labor and 123 were elective. dUCC was performed in 137, eUCC without milking in 53 and UCM in 33 cases. Neonatal Hct was higher in CS carried out in labor versus in elective CS (59.76% ± 6.17 vs 56.91% ± 5.95, P = 0.001). At multivariate analysis, CS performed in labor (coefficient [coeff.] 3.44, confidence interval [CI] 1.75-5.13, P < 0.001), UCM (coeff. 3.88, CI 1.61-6.14, P = 0.001) and birth weight (coeff. -0.003, CI -0.005 to -0.001, P = 0.001) were the only variables independently associated with neonatal Hct. In elective CS, UCM led to higher neonatal Hct (61.5% ± 5.5) compared to eUCC without milking (55.1% ± 5.5) and dUCC (56.4% ± 5.7, P = 0.001), while in CS performed in labor there were no significant differences among the placental transfusion strategies.

CONCLUSION

In term CS, neonatal Hct is significantly higher when the CS is performed in labor or with UCM. In elective CS, UCM could be a valid option to favor placental transfusion.

Umbilical Cord Milking in Infants Born at <37 Weeks of Gestation: A Systematic Review and Meta-Analysis

Umbilical cord milking (UCM) could be an alternative in cases where delayed umbilical cord clamping cannot be performed, therefore our objective was to evaluate the effects of UCM in newborns <37 weeks’ gestation. In this systematic review and meta-analysis, we searched MEDLINE, EMBASE, CINAHL, the Cochrane Database of Clinical Trials, the clinicaltrails.gov database for randomized UCM clinical trials with no language restrictions, which we then compared with other strategies. The sample included 2083 preterm infants. The results of our meta-analysis suggest that UCM in premature infants can reduce the risk of transfusion (relative risk (RR)= 0.78 [95% confidence interval (CI),0.67–0.90]) and increase hemoglobin(pooled weighted mean difference (PWMD)= 0.89 g/L[95%CI 0.55–1.22]) and mean blood pressure (PWMD=1.92 mmHg [95% CI 0.55–3.25]). Conversely, UCM seems to increase the risk of respiratory distress syndrome (RR = 1.54 [95% CI 1.03–2.29]), compared to the control groups. In infants born at <33 weeks, UCM was associated with a reduced risk of transfusion (RR= 0.81 [95%CI 0.66–0.99]), as well as higher quantities of hemoglobin (PWMD= 0.91 g/L[95%CI 0.50–1.32]). UCM reduces the risk of transfusion in preterm infants, and increases initial hemoglobin, hematocrit, and mean blood pressure levels with respect to controls.

Stem Cell Composition of Umbilical Cord Blood Following Milking Compared with Delayed Clamping of the Cord Appears Better Suited for Promoting Hematopoiesis

In comparing placental transfusion strategies, blood obtained from an umbilical cord that has been "milked" vs one in which clamping was simply delayed contains mesenchymal stromal cells in addition to solely hematopoietic stem cells, a composition more favorable for hematopoiesis, as suggested by its superior rescue of lethally irradiated bone marrow-depleted mice.

Effect of timing of umbilical cord clamping and other strategies to influence placental transfusion at preterm birth on maternal and infant outcomes

BACKGROUND

Infants born preterm (before 37 weeks' gestation) have poorer outcomes than infants at term, particularly if born before 32 weeks. Early cord clamping has been standard practice over many years, and enables quick transfer of the infant to neonatal care. Delayed clamping allows blood flow between the placenta, umbilical cord and baby to continue, and may aid transition. Keeping baby at the mother's side enables neonatal care with the cord intact and this, along with delayed clamping, may improve outcomes. Umbilical cord milking (UCM) is proposed for increasing placental transfusion when immediate care for the preterm baby is needed. This Cochrane Review is a further update of a review first published in 2004 and updated in 2012.

OBJECTIVES

To assess the effects on infants born at less than 37 weeks' gestation, and their mothers of: 1) delayed cord clamping (DCC) compared with early cord clamping (ECC) both with immediate neonatal care after cord clamping; 2) DCC with immediate neonatal care with cord intact compared with ECC with immediate neonatal care after cord clamping; 3) DCC with immediate neonatal care after cord clamping compared with UCM; 4) UCM compared with ECC with immediate neonatal care after cord clamping.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (10 November 2017), and reference lists of retrieved studies. We updated the search in November 2018 and added nine new trial reports to the awaiting classification section to be assessed at the next update.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing delayed with early clamping of the umbilical cord (with immediate neonatal care after cord clamping or with cord intact) and UCM for births before 37 weeks' gestation. Quasi-RCTs were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Random-effects are used in all meta-analyses. Review authors assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

This update includes forty-eight studies, involving 5721 babies and their mothers, with data available from 40 studies involving 4884 babies and their mothers. Babies were between 24 and 36+6 weeks' gestation at birth and multiple births were included. The data are mostly from high-income countries. Delayed clamping ranged between 30 to 180 seconds, with most studies delaying for 30 to 60 seconds. Early clamping was less than 30 seconds and often immediate. UCM was mostly before cord clamping but some were milked after cord clamping. We undertook subgroup analysis by gestation and type of intervention, and sensitivity analyses by low risk of selection and attrition bias.All studies were high risk for performance bias and many were unclear for other aspects of risk of bias. Certainty of the evidence using GRADE was mostly low, mainly due to imprecision and unclear risk of bias.Delayed cord clamping (DCC) versus early cord clamping (ECC) both with immediate neonatal care after cord clamping (25 studies, 3100 babies and their mothers)DCC probably reduces the number of babies who die before discharge compared with ECC (average risk ratio (aRR) 0.73, 95% confidence interval (CI) 0.54 to 0.98, 20 studies, 2680 babies (moderate certainty)).No studies reported on 'Death or neurodevelopmental impairment' in the early years'.DCC may make little or no difference to the number of babies with severe intraventricular haemorrhage (IVH grades 3 and 4) (aRR 0.94, 95% CI 0.63 to 1.39, 10 studies, 2058 babies, low certainty) but slightly reduces the number of babies with any grade IVH (aRR 0.83, 95% CI 0.70 to 0.99, 15 studies, 2333 babies, high certainty).DCC has little or no effect on chronic lung disease (CLD) (aRR 1.04, 95% CI 0.94 to 1.14, 6 studies, 1644 babies, high certainty).Due to insufficient data, we were unable to form conclusions regarding periventricular leukomalacia (PVL) (aRR 0.58, 95% CI 0.26 to 1.30, 4 studies, 1544 babies, low certainty) or maternal blood loss of 500 mL or greater (aRR 1.14, 95% CI 0.07 to 17.63, 2 studies, 180 women, very low certainty).We identified no important heterogeneity in subgroup or sensitivity analyses.Delayed cord clamping (DCC) with immediate neonatal care with cord intact versus early cord clamping (ECC) (one study, 276 babies and their mothers)There are insufficient data to be confident in our findings, but DCC with immediate neonatal care with cord intact may reduce the number of babies who die before discharge, although the data are also compatible with a slight increase in mortality, compared with ECC (aRR 0.47, 95% CI 0.20 to 1.11, 1 study, 270 babies, low certainty). DCC may also reduce the number of babies who die or have neurodevelopmental impairment in early years (aRR 0.61, 95% CI 0.39 to 0.96, 1 study, 218 babies, low certainty). There may be little or no difference in: severe IVH; all grades IVH; PVL; CLD; maternal blood loss ≥ 500 mL, assessed as low certainty mainly due to serious imprecision.Delayed cord clamping (DCC) with immediate neonatal care after cord clamping versus umbilical cord milking (UCM) (three studies, 322 babies and their mothers) and UCM versus early cord clamping (ECC) (11 studies, 1183 babies and their mothers)There are insufficient data for reliable conclusions about the comparative effects of UCM compared with delayed or early clamping (mostly low or very low certainty).

AUTHORS' CONCLUSIONS

Delayed, rather than early, cord clamping may reduce the risk of death before discharge for babies born preterm. There is insufficient evidence to show what duration of delay is best, one or several minutes, and therefore the optimum time to clamp the umbilical cord remains unclear. Whilst the current evidence supports not clamping the cord before 30 seconds at preterm births, future trials could compare different lengths of delay. Immediate neonatal care with the cord intact requires further study, and there are insufficient data on UCM.The nine new reports awaiting further classification may alter the conclusions of the review once assessed.

The residual blood from segmental umbilical cord milking in preterm delivery

Umbilical cord milking is an alternative procedure providing blood to infants but there is no study in the proper length of umbilical cord and various gestational age. The aim of this study was to measure the blood volume in the umbilical cord of preterm infants at a certain length and to identify the correlation among blood volume, length, and circumference of umbilical cord, gestational age (GA), birth weight and placenta. Seventy-five pregnant women aged 18 years old and above with 24-36⁺⁶ weeks of gestation were included in this cross-sectional study. After delivery, a 15 to 45 cm of umbilical cord was cut and parameters of umbilical cord were recorded. The mean GA at birth was 241.84 ± 20.06 days. The mean length, diameter, and circumference were 23.31 ± 7.66, 1.10 ± 0.18, and 3.56 ± 0.75 cm, respectively. The mean residual blood volume was 11.58 ± 4.99 mL or 0.50 ± 0.18 mL/cm. Total residual blood volume had a significant positive strong correlation with umbilical cord length (r = 0.720, p < .001). To reduce complications from blood overload, the appropriate blood volume for preterm infant should be calculated from birth weight and umbilical cord length.Impact statementWhat is already known on this subject? The World Health Organisation recommends delayed cord clamping for newborn infants which neonatal resuscitation was not indicated but the majority of preterm infants needed resuscitation. Umbilical cord milking is an alternative procedure providing blood to infants. A small volume transfusion (10-20 m/kg) is commonly used for replacement in preterm neonates. Although there is a concern about the blood volume transferred into infants, blood volume and proper length of umbilical cord have not been thoroughly investigated.What do the results of this study add? In this study, the mean residual blood volume was 0.5 mL/cm and total residual blood volume had a significant positive strong correlation with umbilical cord length. In subgroup of very low birth weight group, the mean residual blood volume was 0.41 mL/cm; however, there was no statistically significant difference from other birth weight groups.What are the implications of these findings for clinical practice and/or further research? The appropriate length of umbilical cord for milking can be calculated from the estimated foetal weight and the mean residual blood volume per length (0.5 mL/cm); nevertheless, the calculation should be used with caution. The further study should investigate in extremely preterm or very low birth weight infants.

Delayed clamping vs milking of umbilical cord in preterm infants: a randomized controlled trial

BACKGROUND

It has been established that delayed umbilical cord clamping in preterm infants results in improvement in neonatal anemia, need for transfusion, incidence of necrotizing enterocolitis, and intraventricular hemorrhage by increasing neonatal circulating blood volume. However, the effects of umbilical cord milking as an alternative to delayed clamping in preterm infants are unclear.

OBJECTIVE

The primary objective of this study was to compare the effect of delayed clamping vs milking of the umbilical cord on the initial hematocrit concentration in preterm births (23-34 weeks gestation). In addition, we sought to compare the effects of delayed clamping vs milking on the incidences of intraventricular hemorrhage, necrotizing enterocolitis, and need for transfusion (secondary objectives).

STUDY DESIGN

The study was an unblinded randomized controlled trial of singleton preterm infants who were born 23 weeks 0 days to 34 weeks 6 days gestation and were assigned to 1 of 2 controlled study groups: delayed cord clamping for 60 seconds or milking of the cord towards the infant 4 times before clamping. Randomization occurred via block randomization with an allocation ratio of 1 to 1. The patients' third stage of delivery was standardized for route of delivery and randomization arm. All comparisons were preformed with an intent-to-treat analysis approach. The study was powered at 80% with a probability value of .05 for the primary outcome measure of a hematocrit difference of 3% between the 2 groups.

RESULTS

Of the 204 randomized patients, 104 were assigned to the delayed subgroup, and 100 were assigned to the milking subgroup. There were no significant differences in baseline maternal characteristics noted between groups. Though there was not any statistically significant difference in neonatal outcomes between the cord clamping and milking groups, the occurrences of transfusion (15.5% vs 9.1%; P=.24), necrotizing enterocolitis (5.8% vs 3.0%; P=.49), and intraventricular hemorrhage (15.5% vs 10.1%; P=.35) were all lower in the milking group. The milking group had higher initial hematocrit concentration compared with the delayed clamping group, although this was not significant (51.8 [6.2%] vs 49.9 [7.7%]; P=.07]. Peak bilirubin levels and need for phototherapy were similar between groups.

CONCLUSION

This study demonstrates that milking the umbilical cord may be an acceptable alternative to delayed cord clamping because there were similar effects on neonatal hematocrit concentrations and the need for neonatal transfusions and no increased risk for complications or neonatal morbidity. The present data support the concept that milking of the umbilical cord may offer an efficient and timely method of providing increased blood volume to the infant.

Umbilical cord milking reduces the risk of intraventricular hemorrhage in preterm infants born before 32 weeks of gestation

OBJECTIVE

Intraventricular hemorrhage (IVH) is a common complication in extremely preterm infants. We aimed to demonstrate that umbilical cord milking (UCM) would reduce the incidence of IVH in this at risk population.

STUDY DESIGN

We compared the incidence of IVH in a prospective cohort of consecutively born preterm infants <32 weeks' gestation receiving UCM (n = 33) with a historical cohort that underwent immediate cord clamping (ICC) (n = 36).

RESULTS

No significant differences regarding perinatal characteristics were present between both groups except for chorioamnionitis and preterm rupture of membranes which were more frequent in the UCM group. There was a significant reduction in the incidence of IVH in the UCM group as compared to the ICC group (UCM vs. ICC = 12 vs. 33%, p = 0.037; OR = 0.276 (95% CI 0.079-0.967; p = 0.033; NNT = 4.7) and a reduction in the number of transfusions (UCM vs. ICC = 56 vs. 30%, p = 0.035; OR = 0.348 (0.129-0.938; p = 0.033; NNT = 3.8). UCM was safe for mothers (similar decrease in maternal hemoglobin) and offspring.

CONCLUSION

UCM significantly reduced the incidence of IVH in preterm infants < 32 weeks' gestation without associated complications for mother or offspring.

Cut umbilical cord milking: an ineffective method of placental transfusion in preterm infants?

Objective: To determine if umbilical cord milking performed on a cut umbilical cord segment increased the hemoglobin/hematocrit, with a reduction in the incidence of intraventricular hemorrhage, need for blood transfusions, and pressor requirement in infants with <35-weeks gestation.Study design: This was a single center, observational study in the NICU. One-hundred-six neonates received cut umbilical cord milking and two hundred ninety seven served as historical controls.Result: There were no statistically significant differences between the two groups in hemoglobin/hematocrit, peak bilirubin values, the incidence of intraventricular hemorrhage, need for blood transfusions, and the use of pressors.Conclusion: This is the first study using the cut umbilical cord milking technique that includes neonates with <35-weeks gestation. The procedure is safe but did not result in an increase in hemoglobin/hematocrit, nor did it reduce the incidence of intraventricular hemorrhage, need for blood transfusions, and pressor use.

Inter-twin hemoglobin difference at birth in uncomplicated monochorionic twins in relation to the size of the placental anastomoses

OBJECTIVE

To evaluate the relation between Hb levels and the size of the placental anastomoses.

METHODS

We performed a retrospective review of all uncomplicated MC twins delivered vaginally at our center from 2002 to 2017. Hb levels at birth and on day 2 were retrieved. All MC placentas were routinely injected with colored dye and high-resolution pictures were taken for computer-based analysis. We measured the size of arterio-arterial (AA) and veno-venous (VV) anastomoses as well as the total venous size, defined as the sum of the diameter of first generation of placental veins within 5 cm of each cord insertion. We assessed the relation between Hb levels and placental angioarchitecture.

RESULTS

A total of 170 MC twin pairs were analyzed. Median Hb level in twin 1 was significantly lower than that in twin 2 both at birth (16.0 versus 17.4 g/dl, P = 0.02) and on day 2 (14.6 versus 18.1 g/dl, P = 0.000000188). Inter-twin Hb difference on day 2 was positively correlated with the size of AA anastomoses (Spearman r = 0.25, 95% CI 0.04-0.43, P = 0.0161). The diameter of AA anastomoses was positively related to the total size of veins connecting to AA anastomoses in the placental territory of twin 2 (Spearman r = 0.55, 95% CI 0.41-0.66, P = 0.0001).

DISCUSSION

MC twins with larger AA anastomoses have higher Hb differences at birth. Higher Hb levels in second born twins may partly be due to increased placento-fetal transfusion through larger placental vessels.

Umbilical Cord Milking: A Review

This is a review of umbilical cord milking, a controversial technique where the umbilical cord is squeezed several times before it is clamped an cut. While not physiological or natural for newborns, the question lies as to whether it is useful in certain circumstances, namely the depressed newborn. Here we review the literature and discuss why it could be considered as an alternative for the current practice of delayed cord clamping.

Haemodynamic effects of umbilical cord milking in premature sheep during the neonatal transition

OBJECTIVE

Umbilical cord milking (UCM) at birth may benefit preterm infants, but the physiological effects of UCM are unknown. We compared the physiological effects of two UCM strategies with immediate umbilical cord clamping (UCC) and physiological-based cord clamping (PBCC) in preterm lambs.

METHODS

At 126 days' gestational age, fetal lambs were exteriorised, intubated and instrumented to measure umbilical, pulmonary and cerebral blood flows and arterial pressures. Lambs received either (1) UCM without placental refill (UCMwoPR); (2) UCM with placental refill (UCMwPR); (3) PBCC, whereby ventilation commenced prior to UCC; or (4) immediate UCC. UCM involved eight milks along a 10 cm length of cord, followed by UCC.

RESULTS

A net volume of blood was transferred into the lamb during UCMwPR (8.8 mL/kg, IQR 8-10, P=0.01) but not during UCMwoPR (0 mL/kg, IQR -2.8 to 1.7) or PBCC (1.1 mL/kg, IQR -1.3 to 4.3). UCM had no effect on pulmonary blood flow, but caused large fluctuations in mean carotid artery pressures (MBP) and blood flows (CABF). In UCMwoPR and UCMwPR lambs, MBP increased by 12%±1% and 8%±1% and CABF increased by 32%±2% and 15%±2%, respectively, with each milk. Cerebral oxygenation decreased the least in PBCC lambs (17%, IQR 13-26) compared with UCMwoPR (26%, IQR 23-25, P=0.03), UCMwPR (35%, IQR 27-44, P=0.02) and immediate UCC (34%, IQR 28-41, P=0.02) lambs.

CONCLUSIONS

UCMwoPR failed to provide placental transfusion, and UCM strategies caused considerable haemodynamic disturbance. UCM does not provide the same physiological benefits of PBCC. Further review of UCM is warranted before adoption into routine clinical practice.

Umbilical cord blood as a source for red-blood-cell transfusion in neonatology: a systematic review

The prevention and treatment of anaemia in newborn patients made tremendous progress in the last decades. However, red-blood-cell (RBC) transfusions remain unavoidable in many neonates candidate to surgery and especially in preterm infants. In particular, anaemia occurring in neonates born at extremely low gestational age is actually severe and frequently requires transfusions. Several approaches have been explored to prevent or even to reduce the threshold and the frequency of RBC transfusions. Among these, umbilical cord blood (UCB) collection and processing to obtain RBC components for autologous or allogeneic transfusion have been extensively investigated. In this systematic review, we revised the literature concerning the use of UCB for either autologous or allogeneic transfusion purposes and we illustrated the rationale for a transfusion therapy tailored to extremely preterm neonates, based on RBC concentrates from allogeneic UCB donations.

Umbilical cord milking for neonates who are depressed at birth: a randomized trial of feasibility

OBJECTIVE

To evaluate the feasibility and safety of umbilical cord milking (UCM) in neonates who are depressed at birth.

STUDY DESIGN

This is a quasi-randomized, non-blinded, controlled trial on infants (≥35 weeks) who were depressed at birth. UCM (cord milked three times) was performed during the even months and the neonates born during the odd months were in the control group. Primary outcome was feasibility and safety.

RESULTS

A total of 101 infants were enrolled (50 UCM group and 51 control group) between January 2015 and October 2016. UCM was performed in 95% of infants (59/62) who qualified to receive UCM. There were no significant differences in resuscitation delay, resuscitation efforts, and short-term outcomes between the two groups.

CONCLUSIONS

UCM is feasible for term and late preterm infants who are depressed at birth. A larger clinical trial is needed to evaluate long-term benefits of UCM in neonates with HIE.

Benefits of umbilical cord milking versus delayed cord clamping on neonatal outcomes in preterm infants: A systematic review and meta-analysis

BACKGROUND

Optimum timing of umbilical cord clamping has not been established in preterm infants.

OBJECTIVES

We compared the short- and long-term effects of umbilical cord milking (UCM) versus delayed cord clamping (DCC) on infants born at less than 37 weeks of gestation.

SEARCH METHODS

A systematic review and meta-analysis was conducted according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" statement. We searched CINAHL, CENTRAL, EMBASE, MEDLINE, PubMed and ClinicalTrials.gov for relevant randomized controlled trials (RCTs).

SELECTION CRITERIA

We included individual and clustered RCTs comparing UCM to DCC for infants born before 37 weeks of gestation.

DATA COLLECTION AND ANALYSIS

Four reviewers independently assessed trial quality and eligibility for inclusion.

MAIN RESULTS

Two trials (255 preterm infants, 23 0/7 to 32 6/7 weeks of gestation) were included in the analysis. UCM was associated with fewer intraventricular hemorrhages (IVHs) (two trials, 255 infants; relative risk [RR] 0.45, 95% confidence interval [CI] 0.20 to 0.98, low quality of evidence) and UCM was an increased proportion of infants with a Bayley score at 2 years of age (two trials, 174 infants; Cognitive: RR 1.14, 95% CI 1.03 to 1.26, Language: RR 1.24, 95% CI 1.03 to 1.49, low quality of evidence) compared to DCC.

CONCLUSIONS

UCM wasn't reduced in-hospital mortality and need for transfusion compared to DCC. But our study suggests that UCM may lower the risk of IVH and improve certain neurodevelopmental outcomes compared to DCC in preterm infants.