The risk of SUDI including SIDS and fatal sleeping accidents is greatest at 2-4 months, although the risk is there for the first 12 months. Babies' sleep environments can increase their risk of SUDI including SIDS and fatal sleeping accidents.
The peak incidence of SIDS occurs between 1 – 4 months of age; 90% of cases occur before 6 months of age. Babies continue to be at risk for SIDS up to 12 months.
SIDS is most common at 2-4 months of age when the cardiorespiratory system of all infants is in rapid transition and therefore unstable. So, all infants in this age range are at risk for dysfunction of neurological control of breathing.
SIDS risk by age
The NICHD notes that SIDS is most common when an infant is between 1–4 months old. Additionally, more than 90% of SIDS deaths occur before the age of 6 months old. The risk of SIDS reduces after an infant is 8 months old.
How often does SIDS occur? SUDI and SIDS are rare and the risk of your baby dying from these is very low. The rate of SIDS deaths has declined in Australia due to safe sleeping campaigns. In 2020, 100 babies in Australia died of SUDI (data from Queensland, New South Wales, Victoria and Western Australia only).
While the cause of SIDS is unknown, many clinicians and researchers believe that SIDS is associated with problems in the ability of the baby to arouse from sleep, to detect low levels of oxygen, or a buildup of carbon dioxide in the blood. When babies sleep face down, they may re-breathe exhaled carbon dioxide.
SIDS has no symptoms or warning signs. Babies who die of SIDS seem healthy before being put to bed. They show no signs of struggle and are often found in the same position as when they were placed in the bed.
White noise reduces the risk of SIDS.
We DO know that white noise reduces active sleep (which is the sleep state where SIDS is most likely to occur).
SIDS usually occurs when a baby is asleep, although it can occasionally happen while they're awake. Parents can reduce the risk of SIDS by not smoking while pregnant or after the baby is born, and always placing the baby on their back when they sleep. Find out how to stop smoking.
Babies need tummy time! Although it does not directly reduce the risk of Sudden Infant Death Syndrome (SIDS), tummy time is an important way to help baby grow and develop.
Infants at the age when SIDS occurs quite frequently spend most of their sleep in a stage known as rapid eye movement or REM sleep. This sleep stage is characterized by the dysregulation of various mechanosensory airway and chemosensory autonomous reflexes that are critical for survival (18, 19).
Breastfeeding has been shown to reduce the occurrence of SIDS by over 50 percent by improving the immune system, promoting brain growth, reducing reflux and a variety of other factors.
Dr. Hauck: We don't know for sure why room-sharing without bed-sharing is protective, but we have some theories. One is that the babies are sleeping more lightly because there is more movement around them (so they cannot get into as deep a sleep, which can contribute to the final pathway in SIDS).
In contrast, the increased risk of SIDS associated with excess thermal insulation and bed sharing was less in winter than in summer. Prone sleeping position accounts for about half of the difference between the mortality rate in summer and that in winter.
Overheating is linked to SIDS, so it's important that you don't bundle your baby too tightly in the winter. Try to keep their room cool in the months when the temperature outside is higher than 70 degrees Fahrenheit. There's some evidence that suggests that high environmental temperatures are also linked to SIDS.
However, 10% of SIDS happens between 6 and 12 months of age and safe sleep recommendations should be followed up to a baby first birthday. By the time a baby turns 12 months old, the risk of sudden death is negligible.
The highest SIDS rates in 1990 (>2.0/1000 live births) were in Ireland, New Zealand, and Scotland. More recently, the highest SIDS rates (>0.5/1000 live births) are in New Zealand and the United States. The lowest rates (<0.2/1000) are in Japan and the Netherlands.
SIDS is not the same as suffocation and is not caused by suffocation. SIDS is not caused by vaccines, immunizations, or shots. SIDS is not contagious.
"SIDS rates are lowest among Hispanic and Asian/Pacific Islander infants." SIDS is also slightly more common in males than females.
As outlined in the review, pacifier use during sleep may improve autonomic control of breathing, airway patency, or both. Further, it has been hypothesized that the pacifier could prevent accidental rolling leading to less risk of SIDS.
Babies might have a higher risk of SIDS if: their mother smoked, drank, or used drugs during pregnancy and after birth. their mother had poor prenatal care. they were born prematurely or at a low birth weight.
Frequent night waking is thought to be protective against SIDS. Studies of near-miss infants and siblings of SIDS infants show that these babies have fewer night-waking episodes.