Milking the Umbilical Cord at Term Cesarean Birth

New evidence suggests the practice of immediate clamping and cutting of the umbilical cord at birth may contribute to anemia in infancy. Immediate clamping can deprive a full term infant of 60 to 100 ml of whole blood representing 30 to 50 mg/kg of iron. The "low tech-low cost" intervention of delayed cord clamping can reduce anemia in infancy by enhancing placental-infant transfusion at birth. The risk of maternal bleeding makes a delay in cord clamping at the time of cesarean section challenging. In the United States (US), immediate clamping and cutting of the umbilical cord is the usual practice at the time of cesarean section. Milking of the umbilical cord may offer an alternative to delayed cord clamping for the prevention of anemia in infancy when time and speed are critical factors at the time of cesarean section. Although some obstetrical and pediatric providers fear adverse outcomes from delayed cord clamping or umbilical cord milking such as polycythemia or jaundice, the most recent clinical trials fail to support these fears.

In spite of iron supplementation and iron fortified formula and food, iron deficiency in infants and toddlers remains a significant public health problem in the US. Poor iron stores in the first year of life can lead to iron deficiency which has the potential to cause harm to the developing brain.

The number of births by cesarean section is on the rise in this country. According to the latest US birth data reported by the National Center for Health Statistics, the cesarean section rate is now above 32%, over a 50% increase since 1996. Immediate cord clamping is routine practice at the time of cesarean section in the US. Consequently over 1.4 million babies annually will have their umbilical cords cut immediately at the time of birth. This routine practice interferes in placental transfusion and results in less blood volume and red blood cells and increases anemia at birth and lowers total body iron stores in the newborn at six months. The potential effect of immediate cord clamping at cesarean section is enormous on the public health of infants in this country. However the association between cord clamping time and infant well-being is not generally recognized by clinicians.

Delaying the clamping and cutting of the cord for just two minutes is known to offer benefit and can improve the iron stores of term newborns extending into at least the first six months of life. Although there is benefit for the baby, a two minute delay is not feasible for the mother at time of cesarean section. However, milking of the umbilical cord at the time of cesarean section may be a viable alternative to delayed cord clamping and may prevent anemia and infant iron deficiency. Most of the available literature on umbilical cord milking was written over 50 years ago. Even so, these studies support the technique as safe for term infants resulting in higher neonatal hemoglobin and hematocrit levels. One recent study found cord milking was beneficial and did not cause harm in very low birth weight preterm infants.

This study will help to establish the feasibility of using umbilical cord milking as an alternative to delayed cord clamping at the time of cesarean section. Umbilical cord milking will be examined as a selective intervention to accelerate placental transfusion when delayed clamping is not ideal. It has the potential to prevent anemia and iron deficiency in infancy in full-term infants born by cesarean section.