Delayed Cord Clamping and Cord Blood Banking
Delayed cord clamping is a practice that is often very important to parents, and since 2012, the American College of Obstetricians and Gynecologists have recommended a delay of at least 30-60 seconds. The World Health Organization recommends a delay of 1-3 minutes for improved maternal and infant health and nutrition outcomes. 1
Potential Medical Benefits of Delayed Cord Clamping
The World Health Organization collated data on the effects of delayed cord clamping on both preterm and term neonates, to form their recommendations.
Substantial evidence for delayed cord clamping was identified from fifteen randomized controlled trials in preterm neonates, born predominantly in high-income countries.
There was considerable heterogeneity between the included studies in the definition of “late” clamping time (from roughly 30 s to 180 s after birth) and positioning of the infant relative to the placenta or uterus before clamping. There was no difference in risk of mortality between preterm infants with delayed or early umbilical cord clamping (13 studies, 668 infants). Preterm infants with delayed umbilical cord clamping had a lower risk of necrotizing enterocolitis (5 trials, 241 infants) and intraventricular haemorrhage (10 trials, 539 infants). Seven randomized trials (392 infants) looked at the need for blood transfusions for anaemia or low blood pressure among preterm infants; on average, there was approximately a 39% reduction in the need for blood transfusion with delayed umbilical cord clamping. Delayed-clamped infants had significantly higher peak bilirubin concentrations as compared to early-clamped infants, in the seven trials (320 infants) reporting this outcome. There was no significant difference in treatment for jaundice between early- and delayed-clamped infants (three trials, 180 infants), though the treatment criteria probably differed between studies and were not always stated. 2
There were also notable health advantages for delayed cord clamping in term deliveries.
Fifteen randomized controlled trials have assessed the effects of umbilical cord clamping time in term infants from low-, middle- and high-income countries. In most trials, early clamping occurred within 15 seconds of birth, while delayed clamping varied between 1 and 5 minutes after delivery, or at the end of umbilical cord pulsations. There was no difference in neonatal mortality (two trials, 241 infants), or rate of admission to intensive care (four trials, 1675 infants) between early- and delayed-clamped infants. Four studies (954 infants) looked at the risk of anaemia at 3–6 months of age among term infants and no significant difference was found in the rates of anaemia between the delayed- and early-clamping groups. Five trials of term infants (1152 infants) measured indicators of iron deficiency at 3–6 months of age. Infants with delayed clamping were significantly less likely to have iron deficiency than early-clamped infants, though there was high heterogeneity in this outcome, probably because of different measures/ definitions of iron deficiency, as well as the age at which it was assessed. Five trials (1025 infants) reported the effect of timing of umbilical cord clamping on the incidence of polycythaemia among term infants, with no difference between delayed and early umbilical cord clamping. Seven randomized controlled trials (2324 infants) examined the risk of receiving phototherapy for hyperbilirubinaemia following delayed umbilical cord clamping in term neonates. In the majority of the studies, the criteria used for phototherapy were not strictly defined. Delayed-clamped infants were significantly more likely to require phototherapy for jaundice, with a risk difference of <2% between early- and delayed-clamped infants. Only one study (365 infants) evaluated neurodevelopment in term infants, and found no significant effect of umbilical cord clamping time on the measures assessed at 4 months of age. 3
Pairing Delayed Cord Clamping with Umbilical Cord Blood Banking
There is a common perception that cord blood banking is not possible after delaying cord clamping. This perception can be rooted in the belief that either no blood (or very little blood) remains in the umbilical cord after delayed clamping, essentially not enough to possibly collect; or it can be based upon the perception that a notable volume of blood remains, but that it would not be a large enough volume to be worth banking, because there will be no medical value in the volume due to low total nucleated stem cell count.
Yet a controlled study performed at two university hospitals in Sweden for the benefit of The National Swedish Cord Blood Bank (NS-CBB) indicates that while the volume of cord blood collected after delayed cord clamping was reduced by a mean difference of 8.1 ml, cell recovery was not diminished in a statistically significant manner. 4 The study did indicate that a lower percentage of these delayed cord clamping samples were ultimately accepted to the public bank, it is also known that public banks maintain a higher total nucleated cell standard than private banks do for preservation because of the demands of allogeneic transplant. The study concluded that cord blood banking is still feasible after delay clamping practices.
With it established that a large enough volume of blood to collect should be present to physically collect and process, the remaining question is the medical viability of this sample. Americord is dedicated to pushing innovation and practices that ensure the highest efficiency in cord blood processing and preservation. These practices and innovative measures position Americord as an ideal cord blood bank for families that desire to both delay cord clamping and bank cord blood.
- Americord’s lab hand-processes cord blood collections. Manual processing can be particularly important in the case of delayed cord clamping, as an individualized approach in the event of lower collection volume enables more efficient processing. Automation is consistent, but less adaptable to collections that are not statistically average.
- Americord is actively researching technological improvements for both cord blood processing and cryo-preservation. The former has the potential to improve our already best-in-industry results in processing whole cord blood to stem cells that are viable for treatment. The latter could result in a greater percentage of these cells remaining viable after freezing, which would, in turn, mean that even smaller samples could become viable for medical treatment.
The decisions and actions of a medical team post-delivery can also have an impact on the viability of a cord blood collection. Americord is dedicated to the people we work with and under no circumstance recommend any collection practices that would interfere with the efforts of a medical team to deliver the highest level of care to mother and infant. We have received feedback from medical professionals and family members that may enable improved collection in the future.
- There is often a “splash” effect at first drawing of cord blood as the blood makes contact with the anticoagulant in the collection bag. This has occasionally resulted in unnecessarily small collections as a medical professional mistakenly believed a larger collection had performed.
- Multiple methods of improving collection volume have been experimented with. It is proven that the effects of gravity can enable larger collections, and if possible, hanging the cord below the placenta (even from the edge of a surface such as a table) can improve collection volume. At least one doctor who cared for an Americord client has “milked” the placenta, which was one step in an exceptional cord blood collection, with regards to volume. While this does require additional effort from a member of the medical team, it may prove valuable to the patients.
Delayed cord clamping is very important to some expecting parents, but those parents should not have to miss the opportunity to better protect their children from the 80+ (and counting) medical conditions that hematopoietic stem cells have been FDA-approved to treat.