SIDS Program Manual SIDS & Infant Death Program Manual and Trainer's Guide Trainer's Guide

What is SIDS?


Baby with nurse

While the cause or causes of SIDS is unknown, there is evidence that some SIDS infants are born with physiological abnormalities that make them more vulnerable to SIDS.3 Studies of SIDS victims have revealed that many of these infants have abnormalities in the part of the brain involved in the control of breathing and waking during sleep.4 Infants born with defects in other parts of the brain or body may also be more prone to a sudden death. Some researchers speculate that these abnormalities may stem from prenatal exposure to a toxic substance or the lack of a vital compound in the prenatal environment such as sufficient oxygen.5

It has been more than 30 years since Congress passed the landmark legislation that gave the NICHD responsibility for SIDS research. Since that time, the focus of research has been in five areas:6

  1. The brain and its control over breathing and body temperature
  2. Infant development, especially in the areas in which development affects infants' natural protective reactions to their environment, such as turning their head and waking response
  3. Infant care and sleep environment
  4. Infection and the body's ability to avoid and recover from infection
  5. Genetics

Early research efforts were based on single-cause theories for SIDS.7 Today, as a result of that time and those efforts, many researchers believe that there is no one cause of SIDS. Instead, researchers take a multifaceted approach that addresses not only the possibility of a number of different causes but a variety of physiological and environmental interactions as well. The leading theory is the Triple Risk Model theory.8