Constipation is a problem for some people with osteogenesis imperfecta (OI). Two studies indicate that children and adults with OI Type III and pelvic malformation are more likely to complain of constipation and abdominal pain. Constipation, in medical terms, is a decrease in frequency of stools or bowel movements with hardening of the stool. As a consequence, people with constipation may feel bloated and have gas but find it difficult to pass stools. Because the stool becomes quite hard, passing it may be uncomfortable and lead to further unwillingness to try, especially in infants and young children. Fecal impaction, or clogging of the bowel with hardened stool, can be a serious complication. Treatment of constipation in people with OI is often challenging.