Delayed umbilical cord clamping improves iron status in 6‐month‐old Mexican infants

Abstract

We determined whether delayed umbilical cord clamping significantly affects the iron status of full-term, normal birth weight infants through 6 months of age. 476 mother-infant pairs recruited at an obstetrics hospital in Mexico City were randomly assigned to receive delayed (DC) or early (EC) umbilical cord clamping (at 2 minutes or 10 seconds after delivery, respectively). Maternal and placental venous blood samples and a newborn capillary sample were collected. Follow-up interviews occurred at 2, 4 and 6 months to collect dietary, morbidity and anthropometric information. At 6 months an infant venous blood sample was taken. A hematological profile was done on all blood samples and plasma was analyzed for ferritin, transferrin receptor and C-reactive protein. 358 mother-infant pairs completed the study to 6 months, at which time DC infants had significantly higher MCV (80.7 vs. 79.5 fL, p = 0.01), ferritin (48.8 vs. 34.7 μg/L, p = 0.0005), and total body iron (340.9 vs. 319.4 mg, p = 0.009). The beneficial effect of DC on iron status was greatest among breastfed infants not receiving formulas or iron fortified milks, infants of iron deficient mothers, and infants with birth weight between 2500 and 3000 g (p < 0.10 for interactions). The increase in body iron due to DC was equal to 1–2 months’ worth of infant iron needs. This would help prevent iron deficiency prior to 6 months of age, at which point iron-fortified complementary foods can be introduced. Funded by the Thrasher Research Fund and the U.S. Fulbright Program.