461 - Deferral of Umbilical Cord Clamping in Full-term Infants at Birth; Is Longer Duration Better?

Publication Number: 1443.461

Dhuha S Z A F. Alajmi, Dalhousie University Faculty of Medicine, Halifax, NS, Canada; Tim Disher, IWK Health Centre, West Porters Lake, NS, Canada; John Fahey, Children's Specialized Hospital, Halifax, NS, Canada; Melissa Brooks, Dalhousie University Faculty of Medicine, Hafifax, NS, Canada; Balpreet Singh, Dalhousie University Faculty of Medicine, Halifax, NS, Canada; Azar Mehrabadi, Dalhousie University, Halifax, NS, Canada; Walid El-Naggar, Dalhousie University, Halifax, NS, Canada

Background:

Background: Deferred cord clamping (DCC) at birth is recommended as the standard of care for full-term infants. However, there is no consensus on its optimal duration.

Objective: To investigate the impact of different intervals to cord clamping on neonatal outcomes of full-term infants.

Design/Methods: A population-based retrospective study including infants ≥37 weeks' gestation born between 2018-2024 in the province of Nova Scotia, Canada. Infants with major congenital anomalies, fetal anemia, born after placental abruption and those who had umbilical cord milking were excluded. Study population was categorized into 3 groups based on the duration to cord clamping (early cord clamping, ECC < 30 sec, short DCC 30-60 sec, long DCC > 60 sec). Maternal and neonatal characteristics and outcomes were compared. Primary outcome was the risk of hyperbilirubinemia treated with phototherapy. Logistic regression models were used to compare the outcomes among the three groups adjusting for prespecified confounders.

Results: A total of 32,577 infants were included at a mean gestational age 39.5 weeks. Of these, 6,536 (29.1%) received ECC, 11,660 (35.8%) received short DCC and 14,381 (44.1%) received long DCC. Maternal and neonatal characteristics are shown in Table 1. Trends of umbilical cord management are shown in Figure 1. After adjustment for potential confounders that occurred before exposures, short and long DCC were not associated with increased phototherapy treatment compared to ECC [aRR (95% CI) 1.02 (0.91 to 1.13) and 1.04 (0.94 to 1.15)]-Table 2. Progressive increase in the duration of cord clamping was associated with decreased rates of resuscitation, NICU admission, hypoglycemia, transient tachypnea of the newborn and increased breastfeeding on discharge. Neither short DCC nor long DCC was associated with increased maternal post-partum hemorrhage or blood transfusion compared to ECC.

Conclusion(s): In this large population-based study, longer durations of cord clamping were not associated with increased hyperbilirubinemia treated with phototherapy or maternal post-partum hemorrhage compared to ECC. DCC was associated with reduced post-natal morbidities but confounding by indication cannot be ruled out.

Table 1: Comparison of maternal, perinatal, and neonatal baseline characteristics
1n|N|%; Dichotomous data presented as n (%), continuous data presented as either mean (SD) or median (IQR).
(n = N Non-missing)


Table 2: Comparison of adjusted neonatal and maternal outcomes
Adjusted models included delayed cord clamping; married | common-law | partnered; parity; # of pregnancies, including the present one; maternal diabetes; maternal hypertension; maternal smoking; any use of cannabis during pregnancy; maternal chronic infection during pregnancy | group B strep; chorioamnionitis; prolonged rupture of membranes; delivery method; meconium stained fluid; sex (male); gestational age; multiple birth; delivery hospital, and small for gestational age ( < 10th percentile). Dependence between twins accounted for using cluster robust standard errors.

Figure 1: Trends of cord management practices over study years