Sudden Infant Death Syndrome (SIDS)

Sudden Infant Death Syndrome (SIDS) is the sudden, unexplained death of a baby younger than one year of age that doesn't have a known cause even after a complete investigation, which includes an autopsy.

Definition and Diagnosis

SIDS is also known as "crib death" because it often occurs when a baby is sleeping in their crib. The diagnosis of SIDS is made when the following criteria are met:

  • The infant is less than one year old.
  • The death is sudden and unexpected.
  • An autopsy does not show an explainable cause of death.
  • A thorough investigation, including a review of the infant's medical history and the circumstances surrounding the death, does not reveal a cause.

Risk Factors

Certain factors can increase the risk of SIDS. These include:

  • Preterm birth or low birth weight.
  • Family history of SIDS.
  • Mother's age (less than 20 years old).
  • Smoking during pregnancy or exposure to smoke after birth.
  • Bed sharing with parents or other children.
  • Sleeping on the stomach or side, rather than back.
  • Overheating (being too warm) while sleeping.
  • Soft bedding, such as pillows, blankets, and soft mattresses.

Prevention

To reduce the risk of SIDS, parents can take several steps:

  • Place babies on their backs to sleep for every sleep.
  • Use a firm, flat mattress in a safety-approved crib with a tight-fitting sheet.
  • Keep soft objects and loose bedding out of the crib.
  • Avoid overheating by keeping the room at a comfortable temperature.
  • Avoid bed sharing with babies.
  • Consider using a pacifier when putting the baby to sleep, as research suggests it may reduce the risk of SIDS.

Investigation and Autopsy

An investigation into a suspected SIDS death typically includes:

  • A thorough review of the infant's medical history.
  • An examination of the scene where the baby was found unresponsive.
  • An autopsy to look for any signs of disease or injury that could have caused the death.

Support and Resources

Families who experience a SIDS loss can find support through various organizations, such as the American Academy of Pediatrics (AAP) and the National Institute of Child Health and Human Development (NICHD), which provide information on SIDS prevention and resources for grieving families.

Frequently Asked Questions (FAQs)

What is Sudden Infant Death Syndrome (SIDS)?
SIDS is the sudden, unexplained death of an infant under one year of age.

What are the risk factors for SIDS?
Risk factors include premature birth, low birth weight, and exposure to tobacco smoke.

Can SIDS be prevented?
While the cause of SIDS is unknown, certain measures like placing infants on their backs to sleep may reduce the risk.

Is SIDS more common in boys or girls?
SIDS is slightly more common in boys than girls.

What is the most common age range for SIDS?
SIDS typically occurs between 1-4 months of age, with the peak risk at 2-3 months.

Are there any warning signs for SIDS?
There are no definitive warning signs, but infants who have had apparent life-threatening events may be at higher risk.

Can breastfeeding reduce the risk of SIDS?
Breastfeeding may have a protective effect against SIDS, although the relationship is not fully understood.

Should infants sleep on their stomachs or backs to reduce SIDS risk?
The American Academy of Pediatrics recommends placing infants on their backs to sleep to reduce the risk of SIDS.

Can sleeping with an infant increase the risk of SIDS?
Sleeping with an infant, especially on a soft surface, may increase the risk of SIDS due to potential suffocation hazards.

Is SIDS related to vaccinations?
There is no established link between vaccinations and an increased risk of SIDS.

Article last updated on: 18th October 2025.
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