“Effect of Gravity on Placental Transfusion”

Introduction

The length of the time a mother can safely hold her newborn before the umbilical cord is clamped is controversial because of the concerns that gravity may decrease the volume of placental transfusion.

Placental Transfusion

•   Delayed cord clamping allows for passage of blood from the placenta to the infant. This passage of blood is known as Placental Transfusion 
•  Blood flow through the umbilical arteries stops about 45 seconds after the birth, but the umbilical vein remains patent longer. 
•  Uterine contractions enhance the transfer of blood, the volume of which has significant physiological benefits to the neonate. Since gravity influences this transfer, raising the newborn above the level of the placenta prevents a normally occurring placental transfusion. Conversely, lowering the newborn below the placental level accelerates the process. 
•  To hold the infant for more than one minute at the level of the vagina (as is presently recommended), on the assumption that gravity affects the volume of placental transfusion. 
•  Placental transfusion may improve circulating volume at birth, which may in turn improve outcome for preterm infants. 

Cord Milking

This is a technique sometimes called as stripping the cord, in which the cord is pinched between the fingers and the hand is then moved towards the baby before releasing the cord. Umbilical cord milking reduces the need for red cell transfusion in Very low birth weight (VLBW) neonates.

Delayed Cord Clamping

Baby is attached to the placenta by the umbilical cord, which has two arteries and a vein. The umbilical cord transfers blood between the placenta and the baby. The umbilical arteries take deoxygenated blood back to the placenta from the baby, and the umbilical vein brings oxygen rich blood from the placenta. A jelly-like substance called Wharton’s jelly surrounds the arteries and veins, giving support to the cord and keeping the arteries and vein open.  

Definition

The ideal timing for umbilical cord clamping has been controversial. After birth, the first intervention with the baby is cord clamping. When clamping is delayed for more than 2-3 minutes, it is known as “Delayed Cord Clamping.”

“Delayed” Cord Clamping Procedure

Delayed cord clamping procedure calls for waiting to cut the cord, rather than doing it immediately on birth. Blood usually ceases to be exchanged between the baby and placenta anywhere from about 3-10 minutes after the birth. At one minute after birth, 80 mL of blood is transferred from the placenta to baby. At three minutes after birth, 100 mL is transferred. One hundred milliliters is about 3 and 1/2 ounces, and this translates into about 30% more blood volume for the baby (and about 60% more red blood cells). If the cord is clamped early, about 1/3 of baby’s blood will be lost in the placenta and cord.

To hold a baby in this position for over one minute, interferes with immediate contact with the mother and it may affect the compliance with the recommendation of delaying cord clamping. Most newborns could be placed immediately after birth on the mother’s abdomen or chest before clamping the umbilical cord, and depending on the mother’s position (if she is lying down, semisitting or sitting), the infant would be 20 to 40 cm above the vaginal level. Position of the newborn baby before cord clamping does not seem to affect the volume of placental transfusion. Mothers could safely be allowed to hold their baby on their abdomen or chest. This change in practice might increase obstetric compliance with the procedure, enhance maternal-infant bonding, and decrease iron deficiency in infancy.

Potential Benefits of Delayed Cord Clamping

At a 30-60 second delay in clamping, the baby potentially gets: 

•   Additional iron stores and less iron deficiency anemia during the first six months to perhaps one year of life. (Infants need iron for physical and mental development. Usually at six months, breastfed babies are given some kind of iron supplementation since breast milk does not contain enough). 
•  Increased blood volume (which allows for better perfusion of organs). 
•  Reduced need for blood transfusion in premature infants. 
•  Decreased incidence of intracranial hemorrhage (bleeding in the brain) in premature infants.

With a Longer Delay in Cord Clamping, You Potentially Get:

•   Increased immunoglobulin (antibody) transfer. 
•  Increased stem cell transfer. (Stem cells are cells that haven’t yet committed to becoming a particular type of cell yet in the body. They have the ability to develop into many different cell types that may be needed anywhere. When needed, they can differentiate into heart cells, blood cells, bone cells, brain cells, and more. They are very valuable cells for the baby to have).

Drawbacks of delayed cord clamping:

•   Cannot resuscitate the baby. 
•  It can cause polycythemia with hyper viscosity 
•  Cannot collect cord blood for banking. 
•  There is an increased risk of jaundice

“Old Way” of Cord Clamping

In “old” cord clamping procedure, there is (was) no regard for waiting to cut the umbilical cord. As soon as the baby is delivered, the cord is cut, usually just in the amount of time it takes to get the baby cradled on one arm and the clamps on the cord. It is an expedient process designed to get the baby moving on to the next step.

Yes, as long as there has been no damage to the placenta. Different physicians who practice this have different approaches. They can deliver the head from the incision and allow the baby to breathe spontaneously while attached, then deliver the rest of the baby. Or they can deliver the baby and hold the baby at or below the placental level for a minute (In C-sections, the position of the baby is likely important because you may not have the rhythmic contraction of the uterus to help propel flow to the baby like you do in vaginal deliveries). They can milk the cord, drawing the blood towards the baby. Keeping the baby attached to the placenta, while removal of the placenta occurs.