Abstract
Infants born by cesarean section (CS) have been reported to have increased intracellular and total body water and have a slower postnatal decline in cell water content compared to vaginally delivered infants. These findings support the hypothesis that delivery-related changes in water compartmentalization will result in postnatal differences in tissue compressibility. In order to test this hypothesis, static and dynamic skin fold thicknesses (SFTs) were obtained in 60 healthy, term, appropriate for gestational age infants between 1 and 60 h of life. Thirty infants were delivered vaginally and 30 by CS. Midtriceps, subscapular and abdominal skin folds were measured twice daily during the first 3 days of life. There were no differences between groups in birth weight, length, head circumference, gestational age, sex or ponderal index. Our results showed that static SFTs were significantly greater in CS than in vaginally delivered infants at birth and remained so throughout the study period. In both groups, static SFTs increased while weight decreased over time. At birth, dynamic SFTs were significantly greater in infants delivered by CS. We speculate that skin fold differences between CS and vaginal deliveries may reflect a different dynamic of perinatal body water distribution. The mechanism underlying the paradoxical increase in static SFTs in both groups is unknown.