Abstract and Introduction

Abstract

S.N., a healthy 22-year-old gravida 2 para 1 at 38 2/7 weeks' gestation, was admitted to the hospital in active labor. Her history and prenatal course were uncomplicated. Contractions began 10 hours before her arrival at the hospital. Her vaginal examination on arrival was 5 cm dilatation, 50% effaced, and -2 station of the vertex, with intact membranes. Her contractions were occurring every 3 to 5 minutes. Shortly after hospital admission, epidural analgesia was initiated at the patient's request. Four hours later, the frequency of her contractions was every 4 to 6 minutes, and a pelvic examination revealed minimal progress at 6 cm dilatation, 80% effacement, and -1 station. In an attempt to increase the frequency of her contractions, an amniotomy was performed and oxytocin augmentation was initiated. An hour later, her contractions were occurring every 3 to 4 minutes, lasting 60 to 90 seconds. Three hours later, she was fully dilated and the baby's head was at +1 station in an occiput anterior position. At this point, she was instructed to begin pushing with each contraction. Twenty minutes later, S.N. gave birth via normal spontaneous vaginal delivery to a healthy baby boy. The umbilical cord was clamped within 30 seconds of birth, which is routine practice at this hospital, and the baby was brought directly to the warmer. There was no previous discussion with S.N. concerning the timing of the umbilical cord clamping. The placenta spontaneously delivered 5 minutes later, at which point routine oxytocin infusion was initiated via intravenous infusion. The baby boy weighed 3075 g and had Apgar scores of 9 and 9, at 1 and 5 minutes, respectively. There were no labial or perineal lacerations, nor excessive bleeding. The mother's blood type was Rh-positive. Breastfeeding was not attempted in the immediate postpartum period because of maternal exhaustion. Postpartum day one, the baby was both bottle-feeding with formula and breastfeeding. The baby's newborn examination and laboratory values were within normal limits. The family left the hospital on the second postpartum day, satisfied and doing well.

Introduction

Cord clamping immediately after birth is a routine obstetric procedure in the United States[1,2] despite a dearth of supportive evidence documenting its benefits. The case described here represents a common scenario in US hospitals, where discussion of the timing of cord clamping is rare. Currently, there is no set practice guideline for practitioners that delineates when this action should be taken. Active management of the third stage of labor—the objective of which is to reduce the risk of postpartum hemorrhage—often includes clamping the umbilical cord within 30 seconds of birth.[3] Several theories about the potential benefits and risks of delaying the clamping of the umbilical cord have been postulated and studied in recent years. This article reviews the benefits of delayed cord clamping, specifically increased hemoglobin (Hgb) and hematocrit (Hct) levels for the neonate with a subsequent reduction in rates of anemia and iron deficiency that may extend into the infant period. We then analyze the potential dangers of delaying cord clamping (i.e., increased rates of pathologic jaundice, polycythemia, and transient tachypnea in the neonate or increased rates of maternal postpartum hemorrhage). We also take into consideration populations for whom delayed cord clamping could provide extra benefit, such as preterm infants and babies born in areas where anemia is endemic.

Between 25% and 60% of the total fetoplacental circulating blood volume is found in the placenta at term.[2,4] Allowing placental transfusion after birth can provide the newborn with a 30% increase in blood volume and up to a 60% increase in red blood cells (RBCs).[5] This physiologic transfusion is, on average, between 19 and 40 mL/kg of birth weight, equivalent to as much as 2% of the newborn's final birth weight.[1,4]