621 - Neurodevelopmental outcomes of small for gestational age preterm infants who received deferred cord clamping at birth

Publication Number: 621.5781

Beth Ellen Brown, Dalhousie University Faculty of Medicine, Charlottetown, PI, Canada; Prakesh S. Shah, Mount Sinai Hospital, Toronto, ON, Canada; Jehier Afifi, Dalhousie University Faculty of Medicine, Halifax, NS, Canada; Seungwoo Lee, Mount Sinai Hospital, Toronto, ON, Canada; Marc Beltempo, McGill University Faculty of Medicine and Health Sciences, Monreal, PQ, Canada; May Khairy, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Walid El-Naggar, Dalhousie University Faculty of Medicine, Halifax, NS, Canada

Background: We have shown in a previous national study that deferred cord clamping (DCC) is associated with decreased odds of death or major morbidity compared to early cord clamping (ECC) in small for gestational age (SGA) preterm infants. The impact on long-term neurodevelopmental outcomes requires further evaluation.

Objective: To compare the long-term neurodevelopmental outcomes in SGA preterm infants who received DCC with those who received ECC at birth.

Design/Methods: A national retrospective cohort study of SGA preterm infants < 29 weeks’ gestation who were admitted to NICUs participating in the Canadian Neonatal Network database between 2015 and 2020, received DCC (≥ 30 seconds) or ECC ( < 30 seconds) at birth, and were followed up in Canadian Neonatal Follow Up Network centers at 18-24 months’ corrected gestational age. The primary outcome was any neurodevelopmental impairment (NDI) defined as cerebral palsy (CP), score of < 85 in any domain of the Bayley Scales of Infant and Toddler Development 3rd Edition (BSITD-III), deafness, or blindness. Secondary outcomes included significant NDI (sNDI) defined as CP with Gross Motor Function Classification System ≥ 3, BSITD-III < 70 in any domain, bilateral blindness, or deafness requiring hearing aids. Multivariable logistic/linear regression models were used to derive adjusted odds ratio and 95% confidence intervals.

Results: 291 infants were included - Figure 1. Maternal and infant baseline characteristics are shown in Table 1. After adjustment for potential confounders on multivariable regression analysis, there was no significant difference in NDI and sNDI between the two groups. However, DCC in SGA infants was associated with decreased odds of mild language impairment (aOR 0.38, 95% CI 0.20,0.72) and moderate to severe motor impairment (aOR 0.31, 95% CI 0.10,0.94).

Conclusion(s): In this first national study of neurodevelopmental outcomes of SGA preterm infants after DCC, the odds of NDI was not significantly different from those who received ECC. However, there were associated improvements in the language and motor domains. Further evaluation from large sample size studies is needed.

Figure 1: Patient flowchart
SGA- small for gestational age; DCC-deferred cord clamping; ECC-early cord clamping

Table 1.
DCC – deferred cord clamping | ECC – early cord clamping | IVH – intraventricular hemorrhage | PVL – periventricular leukomalacia

Table 3: Adjusted neurodevelopmental outcomes at 18-24 months’ corrected age
DCC- deferred cord clamping | ECC-early cord clamping | BSITD-III- Bayley Scales of Infant and Toddler Development 3rd Edition | NDI- neurodevelopmental impairment | sNDI - significant neurodevelopmental impairment |
†Multivariable logistic (or Gamma GLM as appropriate) regression models adjusted for maternal education (>high school vs ≤ high school), magnesium sulfate administration, mode of delivery, out-born status, infant’s sex and gestational age.