doctor Find a doctor

About SIDS: At Risk

What Do We Mean When We Say a Baby is 'At-Risk' for SIDS?

When we talk about risk factors, we are referring to those environmental and behavioral influences or conditions that can provoke ill health. Scientists study one specific characteristic (or group of characteristics) such as sex, age or race and try to determine how much more common that condition (or risk factor) is in a group of people (or population) suffering from a particular disease or physical ailment compared with a population that is not suffering from that disease or ailment. Risk factors are supposed to increase a person's chance of being born with or developing a disease or condition, but there is no way to say that someone will definitely be born with or acquire the condition or disease just because he or she is known to have those risk factors. Any risk factor may be a clue to finding the cause of a disease, but risk factors are not causes. For example, because almost 80 percent of SIDS deaths occur by the age of 6 months, infants in this age group can be considered to be at increased risk.

It is obvious, though, that age is not a cause of SIDS. Scientists are quick to point out that most risk factors are elements over which most of us have no control - factors such as our sex, race, birth weight or birth order; or the age of our mothers when we were born; or our parents' occupations, incomes or education levels.

There are some risk factors, though, that can be controlled. Researchers know that the mother's health and behavior during her pregnancy and the baby's health before birth seem to somehow influence the occurrence of SIDS. Even this information, however, is not reliable in predicting how, when, why, or if SIDS will occur. For example, we know that smoking during pregnancy, maternal age less than 20, poor prenatal care, low weight gain, anemia, use of illegal drugs, and history of sexually transmitted disease or urinary tract infection are associated with a harmful prenatal environment. However, scientists are not prepared to state that smoking causes SIDS, and we know that not every mother younger than age 20 will have a SIDS baby. Furthermore, SIDS occurs in babies whose mothers have never smoked or who are older than age 20. But what scientific studies tell us is that the chance for SIDS to occur is somehow increased if a mother smokes while pregnant or if she is younger than age 20, or has other risk factors.

Although the relationship between these risk factors and SIDS is not yet clear, it is obvious that by refraining from smoking, by eating properly, and by obtaining adequate prenatal care, a mother can increase the chance for a healthy and normal infant. Some recent studies indicate that certain conditions do not seem to increase the risk for SIDS. Based on reports from parents, SIDS infants do not seem to have more colds or fevers than non-SIDS infants. Information gathered from medical records and interviews from parents strongly suggest that there is no association between DPT vaccinations and SIDS. Newborn apnea (temporary stoppage of breathing) does not appear to increase the chance for SIDS. Apnea through the first year of life, however, does continue to be a focus for intense scientific investigation.