A Study of Factors Affecting Time of First Stool in Premature Infants

ABSTRACT

PURPOSE: To assess the effect of gestational age and illness severity, and the effect of antenatal exposure to magnesium sulfate, glucocorticoids, and antibiotics, on the timing of the first stool in preterm infants. METHODS: Medical records of all preterm infants admitted to the neonatal ward at Kangnam Sacred Heart Hospital between March 1998 and August 1998 were reviewed. We studied the time of the first stool in 55 infants. RESULTS: The median age of the infant at the time of first stool was 18 hours, and 90% of the infants passed stool by 50 hours. Both the gestational age and the illness severity, as measured by the score for neonatal acute physiology(SNAP), correlated significantly with the timing of the first stool(r=0.47 and P<0.001 for SNAP; r=0.29 and P<0.05 for gestational age). An analysis of covariance showed that the relationship between SNAP and the timing of the first stool was significant even after adjustment for gestational age(P<0.01), but the relationship between the gestational age and the timing of the first stool was not significant after adjustment for SNAP (P=0.14). Antenatal exposure to magnesium sulfate for tocolysis, glucocorticoids for enhancing fetal lung maturity, and antibiotics, had no effect on the timing of the first stool. CONCLUSION: Delayed passage of first stool is a function of illness severity, not of gestational immaturity. Antenatal exposure to magnisium sulfate, dexamethasone, and antibiotics, does not affect the timing of first stool in premature infants.