Sudden infant death is not very likely and occurs in about 1 out of every 2,000 live births in the United States.
The highest risk of a baby dying as a result of SIDS is when the baby is between 2 months to 4 months old.
The main risk factors of SIDS or sudden infant death syndrome include the baby sleeping on their stomach or side, which raises the danger and risk of SIDS< soft mattresses, loose blankets and stuffed toys, smoking during pregnancy or after pregnancy and birth factors like premature birth and low birth weight, which all increase risk of SIDS.
To reduce the risk of SIDS in your baby always place your baby on their back to sleep and use a firm, flat mattress with a fitted sheet and keep the baby's crib clear of any toys, pillows and loose blankets and share a room with your baby, but keep your baby in their own separate crib or bassinet.
The number one cause of infant death in the United States is congenital malformations (birth defects), which is what accounts for around 20% of all infant deaths.
Structural or chromosomal abnormalities that are present at birth are also the top driver and cause of deaths in infants before an infant's first birthday.
The top 5 causes of infant death include:
Maternal pregnancy complications, which include health issues that affect the mother or the baby during gestation.
Unintentional injuries like accidental suffocation, strangulation in bed or transport accidents.
SIDS or sudden infant death syndrome, which is unexplained death of an infant during sleep.
Preterm birth, which involves low birth weight and short gestation periods.
And birth defects like structural or chromosomal abnormalities like congenital heart defects.
The most common type of sudden unexpected infant death is SIDS, which stands for sudden infant death syndrome.
SIDS or sudden infant death syndrome accounts or a large portion of cases in which a baby under 1 year of age passes away or dies suddenly, with no clear cause found for the death even after a full investigation has been done.
The key types of Sudden infant death or SUID include:
SIDS, which is the sudden death of a baby that remains unexplained after an autopsy is done on the baby after death as well as after a check of the scene and family history review.
Accidental suffocation and strangulation in bed or ASSB is also a type of death that occurs in babies which is caused by things such as soft bedding, an adult body, or getting trapped in an unsafe sleep area.
And unknown or ill defined causes of infant death also occur in cases when the cause of death of the infant cannot be fond because of tests or investigations not being completed or remaining inconclusive.
SIDS or sudden infant death syndrome most often occurs when a baby is between the ages of 2 months and 4 months of age.
Most of the sudden deaths of babies occur when the baby is sleeping.
And placing the baby to sleep on their back on a firm and flat mattress also helps to lower the risk of SIDS.
Sudden Infant Death Syndrome (SIDS) peaks between the ages of 2 and 4 months of age because this is age in infants a critical window of rapid, unstable development in the infant brain and nervous systems that control breathing, heart rate, and waking up from sleep.
Brain and Body Development:
Breathing Control: The part of the infant brain that handles breathing patterns and reflex responses changes rapidly during these early months.
Sleep Transitions: Babies undergo major shifts in their sleep architecture and arousal responses, making it harder for some infants to wake up if they stop breathing.
Unstable Systems: Cardiorespiratory and blood pressure controls are in a fast transition phase, creating a temporary window of physical vulnerability.
External Stressors:
Environmental Pressures: Underlying brain immaturity combined with external stressors—like soft bedding, face-down sleep positions, or a minor cold—can overwhelm a baby's fragile defense systems during this peak period.
1000 Days/Safe Sleep: Guidance from organizations like the National Institutes of Health Safe to Sleep Campaign emphasizes strict safe sleep practices until 1 year of age, even though the highest risk window passes after 6 months.