When a toilet-trained child suddenly starts pooping in her pants again, she could be suffering from encopresis, a chronic form of constipation that leads to accidents.
Most common in toddlers, the problem often starts when a child has a painful bowel movement and then holds poop in to avoid another uncomfortable experience. (Some kids may stop going in response to a stressful situation.) Eventually, the stool builds up and looser poop leaks around the blockage. Over time, a child may lose the urge to go altogether, creating a vicious and embarrassing cycle -- and that's why it's so important to seek help from your pediatrician. He can prescribe medication to relieve and prevent constipation, as well as give you advice on how to restore your child's potty confidence without guilt or shame.