SUID is the event; SIDS is one possible conclusion.
SIDS is a diagnosis after a thorough investigation remains inconclusive. Different investigation and reporting practices can affect the numbers we see.
CDC explanation →The evidence
What we know. What we are still trying to learn.
Seriousness means saying both clearly. A promising research result is not a test a family can rely on today.
Investigation completeness varies.
In 2020–2024 CDC registry data, 23% of cases were categorized as unexplained with incomplete case information. Autopsy and investigation were recorded for 98% of cases each. That difference is precisely why we must measure completeness rather than whether an autopsy happened.
Read the CDC analysis →Early-life metabolic patterns may hold clues.
Studies of newborn blood spots suggest possible associations with later SIDS. They require independent validation and proof that any resulting action helps infants before they can become a screening tool.
Read the NICHD assessment →Genetic findings may explain a subset of deaths.
Genetic variants are not a universal explanation. Clinical meaning can be uncertain; appropriate interpretation and family follow-up matter.
Read a genetic evaluation study →Evidence page reviewed September 2026. We will document corrections and updates as the organization develops its scientific review process.