Background: Caesarean section rates have increased in parallel with those of obesity. Decreased levels of adiponectin, an adipocyte-derived metabolic hormone present in abundant concentrations in cord blood and breast milk, have been documented in association with obesity in children and adults. Objective: To determine whether the mode of delivery affects adiponectin concentrations in cord blood of healthy term infants. Methods: The cord blood adiponectin concentration was measured in 159 consecutive term infants, of whom 131 (82.4%) were born by vaginal delivery, 15 (9.4%) by nonelective caesarean section and 13 (8.2%) by elective caesarean section. Results: The mean adiponectin level was significantly lower in infants born by elective caesarean section compared with those born by vaginal delivery: 15.3 µg/ml (SD = 6.8) and 21.6 µg/ml (SD = 7.3), respectively (p = 0.015). This difference remained significant after adjustment for the infants' gender and birth weight as well as maternal weight and weight gain during pregnancy. Conclusion: Elective caesarean section may carry a risk of obesity independently of maternal risk factors.