The Effects of Placental Transfusion on 12‐Month Brain Myelin Content in Term Infants: A Randomized Controlled Trial

Abstract

IntroductionImmediate cord clamping (ICC) continues to be the standard practice in the United States. This results in leaving about 30% of the fetal‐placental iron‐rich blood behind in the placenta and puts an infant at risk for lower iron stores. Evidence (animal and human) suggests iron is critical to early brain white matter development as it plays a significant role in myelin formation. The purpose of this study was to determine, at 12 months of age, if infants who received a full placental transfusion at birth differ in myelin content and developmental outcomes compared to infants who received no placental transfusion. The hypothesis was that healthy, term infants who received a full placental transfusion via delayed cord clamping (DCC) will have greater brain myelin content and better neurodevelopmental outcomes compared to infants who received no placental transfusion (ICC) at 12 months of age.MethodsSeventy‐three term pregnant women with singleton fetuses were enrolled in a prospective randomized controlled trial and randomized to either ICC (< 20 s) or DCC (≥ 5 min). At 4 and 12 months, the infants’ hemoglobin and ferritin levels were measured, and the infants underwent a non‐sedated MRI and neurodevelopmental testing.ResultsMaternal and infant demographics were not different between groups. Mean (SD) cord clamping time was 318 (158) seconds in the DCC group versus 10 (5) seconds in the ICC group (P < .0001). At 4 months, infants who received DCC had higher ferritin levels (91 [57] vs 61 [30] ng/mL, P < .04). At 12 months, infants randomized to DCC had significantly greater brain myelin content in the following brain regions: left and right (R) internal capsule, R parietal, R occipital, R frontal, and R orbital areas. The DCC group had a slightly higher social‐emotional performance than the ICC group using the BITSEA Competence score (17 [3] vs 15 [3], P = .08). No differences were seen in ferritin or hemoglobin levels between groups at 12 months.DiscussionAt 12 months, placental transfusion at birth appears to increase brain myelin content in regions involving motor and visual/spatial pathways and sensory processing. Neurodevelopmental testing suggests a trend of better social‐emotional outcomes associated with DCC. In conclusion, the endowment of iron‐rich blood obtained through DCC may offer a longitudinal advantage for early white matter development in the brain.