Colic Causes and Risk Factors

The cause for colic is unknown. There are a number of theories, many of which require more research. Studies have shown that colic is not related to poor parenting skills or associated with a difficult temperament later in life. However, a colicky baby can have a substantial impact on family function, especially as anxiety and fatigue increase.

Possible causes for infantile colic include the following:

  • Abdominal discomfort and intestinal gas (e.g., caused by abnormally rapid digestion [hyperperistalsis], or high levels of intestinal hormones, such as motilin)
  • Allergy or intolerance to formula or breast milk
  • Hunger or overfeeding
  • Immature digestive system or central nervous system
  • Oversensitivity to stimulation (e.g., activity, excitement, anxiety)

Low birth weight increases the risk for infantile colic. Research has shown that infants who weigh less than 5 pounds 8 ounces (about 2500 grams) at birth develop colic approximately twice as often other infants. Premature birth, also called pre-term birth, increases the risk for low birth weight. Infants born before 37 completed weeks of pregnancy are considered premature. Multiples (e.g., twins or triplets) and infants born with certain birth defects or infections (e.g., cytomegalovirus, rubella, chickenpox) are also at increased risk for low birth weight.

Several maternal factors can increase the risk for low birth weight. These factors include the following:

  • Alcohol use
  • Illegal drug use
  • Inadequate weight gain (more common in women under the age of 17)
  • Infections (e.g., urinary tract infection [UTI])
  • Medical conditions (e.g., high blood pressure; diabetes; heart, lung, or kidney problems)
  • Small stature
  • Smoking

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 27 Aug 2008

Last Modified: 04 Sep 2015