OBJECTIVE: To compare death or severe neurodevelopmental impairment (NDI) at 22-26 months corrected age (CA) among extremely preterm infants following exposure to different forms of umbilical cord management. DESIGN: Retrospective study. SETTING: Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network registry. PATIENTS: Infants born <27 weeks gestation in 2016-2018 without severe congenital anomalies who received active treatment after birth and underwent neurodevelopmental assessments between 22 and 26 months CA. EXPOSURES: Immediate cord clamping (ICC), delayed cord clamping (DCC) or umbilical cord milking (UCM). MAIN OUTCOMES AND MEASURE: Primary composite outcome of death or severe NDI at 22-26 months CA, defined as severe cerebral palsy, Bayley-III cognitive/motor composite score <70, bilateral deafness or blindness; individual components were examined as secondary outcomes. Multivariable regression examined associations, adjusting for risk factors identified a priori and potential confounders. Mediation analysis explored the effect of severe intraventricular haemorrhage (IVH) on the exposure-outcome relationship. RESULTS: Among 1900 infants, 64.1% were exposed to ICC, 27.8% to DCC and 8.1% to UCM. Compared with ICC-exposed infants, DCC-exposed infants had lower odds of death or severe NDI (adjusted OR 0.64, 95% CI 0.50 to 0.83). No statistically significant differences were observed when comparing UCM with either ICC or DCC, or between secondary outcomes across groups. Association between cord management and the primary outcome was not mediated by severe IVH. CONCLUSION: Compared with ICC, DCC exposure was associated with lower death or severe NDI at 22-26 months CA among extremely preterm infants, which was not mediated by severe IVH.

Objective

To compare short-term outcomes after placental transfusion (delayed cord clamping (DCC) or umbilical cord milking (UCM)) versus immediate cord clamping among extremely preterm infants.

Design

Retrospective study.

Setting

The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network registry.

Patients

Infants born <29 weeks' gestation in 2016 or 2017 without congenital anomalies who received active treatment after delivery.

Intervention/exposure

DCC or UCM.

Main outcome measures

Primary outcomes: (1) composite of mortality or major morbidity by 36 weeks' postmenstrual age (PMA); (2) mortality by 36 weeks PMA and (3) composite of major morbidities by 36 weeks' PMA. Secondary composite outcomes: (1) any grade intraventricular haemorrhage or mortality by 36 weeks' PMA and (2) hypotension treatment in the first 24 postnatal hours or mortality in the first 12 postnatal hours. Outcomes were assessed using multivariable regression, adjusting for mortality risk factors identified a priori, significant confounders and centre as a random effect.

Results

Among 3116 infants, 40% were exposed to placental transfusion, which was not associated with the primary composite outcome of mortality or major morbidity by 36 weeks' PMA (adjusted OR (aOR) 1.26, 95% CI 0.95 to 1.66). However, exposure was associated with decreased mortality by 36 weeks' PMA (aOR 0.71, 95% CI 0.55 to 0.92) and decreased hypotension treatment in first 24 postnatal hours (aOR 0.66, 95% CI 0.53 to 0.82).

Conclusion

In this extremely preterm infant cohort, exposure to placental transfusion was not associated with the composite outcome of mortality or major morbidity, though there was a reduction in mortality by 36 weeks' PMA.

Trial registration number

NCT00063063.

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.