Delayed cord clamping lowers risk for iron deficiency in newborns
MedWire News: Waiting at least 3 minutes before clamping the umbilical cord in newborn babies could lower their risk for iron deficiency at 4 months, according to a BMJ study.
The practice, known as delayed cord clamping, is not associated with adverse clinical effects, and should be considered as standard of care for all full-term deliveries after uncomplicated pregnancies, say Ola Andersson (Uppsala University, Sweden) and co-authors.
Their study included 400 full-term babies born after a low-risk pregnancy, who were randomly allocated to undergo delayed umbilical cord clamping (≥180 seconds after delivery) or early clamping (≤10 seconds after delivery).
At 4 months of age, there was no significant difference in hemoglobin concentration between the two groups of babies.
However, babies who underwent delayed cord clamping had a significant 45% higher mean concentration of ferritin (an indicator of iron status) and a significant 10% lower risk for iron deficiency, than those who underwent early clamping.
Indeed, the mean ferritin concentration in the group that underwent delayed cord clamping was 117 µg/L, compared with 81 µg/L in the group that underwent early clamping. And the prevalence of iron deficiency in the group that underwent delayed clamping was 0.6% versus 5.7% in the group that underwent early clamping.
Babies who underwent delayed cord clamping also had a significant 20% reduced risk for neonatal anemia at 2 days of age compared with those who underwent early clamping.
The prevalence of neonatal anemia at 2 days of age was 1.2% in the group who underwent delayed cord clamping, compared with 6.3% in the group that underwent early clamping.
There were no significant differences between the groups in terms of postnatal adverse clinical outcomes including respiratory symptoms, polycythemia, or hyperbilirubinemia requiring phototherapy.
The authors estimated that for every 20 babies who underwent delayed clamping, one case of iron deficiency was prevented, regardless of whether the baby also had anemia.
Iron deficiency has been associated with impaired neurodevelopment and psychomotor function in previous studies, emphasizing the importance of delayed cord clamping, the authors write.
They also point out that although the current study was carried out in Sweden, a high-income country, previous studies conducted in low- or middle-income countries have also found a similar effect of delayed cord clamping on ferritin levels, reiterating that the effect is clinically relevant and should lead to a change in practice.
"Further studies are needed to explore long term health effects of delayed and early cord clamping," they conclude.
In a related commentary, editorialist Patrick van Rheenen (University of Groningen, the Netherlands) agrees that the balance between maternal risks and infant benefits of delayed cord clamping "clearly favours" the child.
"How much more evidence is needed to convince obstetricians and midwives that it is worthwhile to wait for three minutes to allow for placental transfusion, even in developed countries?" he asks.
van Rheenen concludes: "Andersson and colleagues' study is convincing enough to encourage a change of practice."
By Piriya Mahendra