Immediate cord clamping is part of routine obstetric procedure in the US. This is part of active management of the third stage (third stage being the time from delivery of the baby to the delivery of the placenta), which is considered optimal for reducing risk of postpartum hemorrhage. The cord is often clamped within 30 seconds of birth. However, there is no practice guideline that indicates when cord clamping should optimally occur. A guideline for what 'delayed' is does not exist either. The various research studies on delayed cord clamping use different time intervals, anywhere from 60 seconds to 3 minutes.
Anywhere from 25% to 60% of the baby's blood volume can be found in the placenta at term. Allowing this blood to return to the baby's circulation after birth can provide the baby with a 30% increase in blood volume and up to a 60% increase in red blood cells. This blood volume increase can contribute as much as 2% of the baby's weight!
The benefits
- Waiting 1-3 minutes in term babies has been shown to result in an increase in Hemoglobin and hematocrit, meaning lower rates of anemia in newborns
- The difference in Hemoglobin and hematocrit continued to be significant at 2 months and 6 months after birth
- Ferritin (iron) stores were significantly higher at 2-3 months of age in infants where delayed cord clamping had occurred
- Delayed cord clamping can increase the rate of hematopoietic stem cells to the newborn, which may play a role in reducing certain blood and immune disorders
The down side
- There is potential for polycythemia (the infant's blood becomes overly thick due to the increase in volume). The studies done on this show mixed results. However, of significance is the finding that no polycythemic infants were symptomatic or required treatment
- Several studies again show mixed results regarding hyperbilirubinemia (elevated bilirubin levels cause jaundice and sometimes require treatment with phototherapy).
- Transient tachypnea (faster than normal respiratory rate in the newborn) may occur as a result of delayed lung fluid absorption casued by an increase in blood volume realted to delayed cord clamping. One study showed that no additional respiratory support was necessary in these infants while another study showed that similar numbers from each group (delayed versus immediate clamping) reuired additional support
FYI
- Immediate cord clamping is not formally a component of active management for prevention of postpartum hemorrhage. Research provides no evidence that this practice increases the risk of hemorrhage
- There is some question of where the newborn should be placed to allow optimal transfusion of placental blood. Not much research has been done on this particular topic.
The midwives of Bethany Womens Healthcare routinely delay cord clamping :)
Eichenbaum-Pikser, G. & Zasloff, J. (2009). Delayed Clamping of the Umbilical Cord: A review with implications for practice. Journal of Midwifery & Women's Health, 54(4), p321.
No comments:
Post a Comment