Timing of passage of first meconium and stooling pattern in normal Nigerian newborns

Background: The time of passing meconium and the subsequent stooling pattern is an important marker in the diagnosis of colonic motility problems in newborns, particularly in Hirschsprung's disease (HD). Method: A cross-sectional study of the passage of meconium and stooling pattern in 280 normal newborns was undertaken using questionnaires administered to mothers attending a postnatal clinic. Results: There were 143 boys and 137 girls aged 6-49 days (median 19 days); 266 (95%) had been full-term infants, 252 (90%) normal deliveries and 28 (10%) delivered by caesarean section. The birthweight of 25 (9%) had been <2.5 kg. Of 267 infants whose mothers knew the time of first passing meconium, it had been delayed for up to 48 hours in 45 (16.9%) and up to 72 hours in 15 (5.6%), and six (2.2%) passed meconium after 72 hours. Overall, 201 (75.3%) passed meconium within 24 hours of birth, 246 (92.1%) within 48 hours and 261 (97.8%) within 72 hours. Irrespective of the time of passing meconium, 80 (31%) infants continued to pass stools at least once daily, 107 (42%) twice daily and 65 (24%) three or more times daily. Only 11 infants were on artificial milk along with breast milk; the remainder were exclusively breastfed. Mode of delivery, birthweight and artificial milk had no effect on time of passing meconium and the subsequent stooling pattern. Conclusion: This study has shown that only 76% of normal infants passed first meconium within 24 hours and, by 3 days of life, a small minority still had not passed meconium. Nearly all normal infants being breastfed should defaecate at least once daily. These findings should be useful in the evaluation of newborns suspected to have HD in this and similar settings.