Colic is defined as inconsolable crying in an infant for at least three hours a day, at least three days a week, for at least three weeks. A colicky baby typically presents with a loud piercing cry, flexed legs, tensed abdominal muscles, and clenched fingers. It typically starts around three weeks of age and lasts until around three months but sometimes lasts for as long as six months. Approximately 10-20% of babies are affected by colic. Doctors diagnose colic based on the previously mentioned "Rule of 3" and after ruling out diseases that may make a baby cry uncontrollably. Parents of infants with colic report significantly higher stress levels than parents whose babies don't have colic. The stress and frustration of trying to soothe a colicky baby may interfere with mother-baby bonding and can increase the risk of postpartum depression. In addition, colicky babies are more likely to be victims of child abuse and shaken baby syndrome. Despite the research done on colic there is no known cause, which can make treatment difficult. Chiropractic care has shown some of the best results, with 94% of colicky babies demonstrating improvement with chiropractic adjustments.