Sudden infant death syndrome (SIDS)

Overview

Sudden Infant Death Syndrome (SIDS) is the unexpected and unexplained death of an apparently healthy baby, typically occurring between 1 month and 1 year of age, even after thorough investigation. The precise cause remains unknown, but it is thought to involve dysfunction in the brain regions responsible for regulating breathing and arousal during sleep.

Often referred to as crib death, SIDS commonly occurs while babies are sleeping, especially during the hours between midnight and 6 a.m. It’s essential to understand that cribs themselves do not cause SIDS; rather, sleep positioning can significantly impact the risk. Placing infants on their backs to sleep is the most effective preventive measure. Additional risk factors include maternal smoking during pregnancy and overheating.

Symptoms

Sudden infant death syndrome is, by definition, an unexplained death, which majority of the cases has no symptoms. 

Causes

The exact cause of sudden infant death syndrome (SIDS) remains unknown, but researchers have explored potential factors contributing to SIDS. An infant is susceptible to SIDS due to both physical and sleep issues.

Researchers believe infants affected by SIDS might have difficulties responding to these triggers and regulating essential bodily functions like breathing and heart rate.

• Physical:
  • Defects in the brain: The area of the brain that regulates breathing and awakening from sleep is underdeveloped in many infants. This birth defect increases infant’s risk of SIDS. 
  • Respiratory illness: A cold can cause breathing issues, which might be connected to SIDS.
  • Low birth weight: Less control over physiological functions like breathing and heart rate is possible among newborns who are underdeveloped at birth or part of a multiple birth.
• Sleep:
  • Overheating: The likelihood of SIDS increase with excessive warmth during sleep. 
  • Sleeping on the side or stomach: Newborns may encounter difficulty of breathing when sleeping in these positions. 
  • Sleeping on a soft surface: An infant’s airway can become obstructed while they are face down on a waterbed, soft mattress, or fluffy blanket.
  • Bed-sharing: If a newborn shares a bed with their parents, siblings, or pets, their risk of SIDS increases. Sleeping in the same room but different bed can reduce SIDS risk. 

Risk factors

Sudden infant death syndrome cannot be prevented. However, certain factors may influence one’s risk of experiencing it. Generally, mothers influence their babies’ risk SIDS during pregnancy, particularly if they are younger than 20 (teen pregnancy), smoke cigarettes, use drugs or alcohol, late or did not receive prenatal care.

Other risk factors include:

• Age: Newborns in their second and fourth months of life are more susceptible to SIDS. 
• Gender: SIDS is more likely to occur in boys than girls.
• Family medical history: Having an immediate family member died of SIDS increases one’s risk. 
• Ethnicity: SIDS disproportionately affects Black, Native American, and Alaska Native infants.
• Premature birth: The risk of SIDS increases in babies born prematurely with low birth weight.
• Secondhand smoke: Exposure to cigarette smoke increases the infant’s risk of SIDS.