As many as 50 percent of people with chronic constipation have pelvic floor dysfunction (PFD) — impaired relaxation and coordination of pelvic floor and abdominal muscles during evacuation. Straining, hard or thin stools, and a feeling of incomplete elimination are common signs and symptoms. But because slow transit constipation and functional constipation can overlap with PFD, some patients may also present with other signs and symptoms, such as a long time between bowel movements and abdominal pain.