Low Cord Ghrelin Levels in Term Infants Are Associated with Slow Weight Gain Over the First 3 Months of Life

Lower ghrelin levels have been related to slower growth in small for gestational age infants, and infants with higher cord leptin levels have been reported to gain weight more slowly from birth to 2 yr. This study investigated whether cord blood ghrelin and leptin levels are related to weight gain up to 12 wk of age. One hundred infants were weighed at birth and at 12 wk, and cord blood was assayed for ghrelin and leptin. The mean (+/-sd) birth weight was 3.458 (0.433) kg (median, 3.390; range, 2.510-4.615 kg). The mean (+/-sd) leptin level was 10.1 (6.7) ng/ml (median, 8.4; range, 1.6-36.7 ng/ml), and that of ghrelin was 760.9 (282.9) pg/ml (median, 770; range, 210-1670 pg/ml). Higher birth weight was associated with slower weight gain. Leptin was correlated with birth weight, but ghrelin was not, and leptin and ghrelin levels were not significantly correlated with one another. With birth weight as a control variable, ghrelin was significantly associated with slow weight gain (chi(2) = 7.20 with 1 df; P < 0.01), although leptin was not (chi(2) = 1.59 with 1 df; P > 0.1). In conclusion, lower cord ghrelin levels are associated with slower weight gain from birth to 3 months of age.