RESUMEN
AIM: During infancy bowel habits change. Most infants with gastrointestinal problems have a functional gastrointestinal disorder (FGID), a major reason for visiting paediatricians. This study aims to provide data on stool frequency and consistency during the first year, prevalence rates for functional constipation (FC) and to establish associations with relevant demographic data. The occurrence of infant colic (IC) and infant dyschezia (ID) was also reported. METHODS: This prospective observational birth-cohort study enrolled 122 healthy full-term infants. Questionnaires were completed at 2 weeks and 2, 6 and 12 months. RESULTS: Stool frequency decreased with age and consistency changed, with fewer runny stools. At 2 weeks, 24.3% had at least one of the studied FGID. FC was found in 2.6%-14.3% (up to 12 months), IC was found in 4.9%-3.4% (up to 2 months) and ID in 22.1%-3.9% (up to 6 months). Infants with an FGID had a lower weight and more healthcare visits than infants without. Breastfeeding and a high percentage of runny stools at 2 weeks of age decreased the odds of developing FC. CONCLUSION: Data on bowel habits and the prevalence of FC, IC and ID are presented. FGID during infancy is common and affects children's well-being, while their families need support and advice.