SUID, SIDS, SUDC, Fetal Death, Infant Mortality, Stillbirth, & Miscarriage
Sudden infant death syndrome (SIDS) is the sudden death of an infant under age 1 that cannot be explained after a thorough investigation has been conducted, including a complete autopsy, an examination of the death scene, and a review of the clinical history.
See Centers for Disease Control and Prevention (CDC), Sudden Unexpected Infant Death (SUID) and Sudden Infant Death Syndrome (SIDS): About SUID and SIDS for expanded information on terminology.
SUID is the sudden and unexpected death of an infant in which the manner and cause of death are not immediately obvious prior to investigation.
How are SUID and SIDS different? SUID can be caused by metabolic disorders, hypothermia or hyperthermia, neglect or homicide, poisoning, or accidental suffocation. Some SUIDs are attributed to SIDS. Sometimes the cause is unknown. In 2004, about 4,600 U.S. infants died suddenly of no immediately obvious cause, and nearly half of these SUID deaths were attributed to SIDS.
The SIDS rate has been declining significantly since the early 1990s. However, CDC research has found that the decline in SIDS since 1999 corresponds to an increase in SUID rates (e.g., deaths attributed to overlaying, suffocation, and wedging) during the same period.
This change in the classification of SUID can be explained by changes in how investigations are conducted and how SUID is diagnosed. (Centers for Disease Control and Prevention, Sudden Unexpected Infant Death (SUID) Initiative.)
SUDC is the sudden and unexpected death of a child over the age of twelve months, which remains unexplained after a thorough case investigation is conducted. This must include: examination of the death scene, performance of a complete autopsy, and a review of the child and family’s medical history. SUDC is a diagnosis of exclusion - given when all known and possible causes of death have been ruled out. (The CJ Foundation for SIDS and the SUDC Program)
Fetal death is defined as the loss of a fetus at any time during pregnancy, not including induced abortions. (Emedicine, WebMD).
Also see the American Academy of Pediatrics' Standard Terminology for Fetal, Infant, and Perinatal Deaths (2011) which discusses terminology and reporting requirements.
Both “miscarriage” (also known as spontaneous abortion) and “stillbirth” are terms describing fetal death, but they refer to losses that occur at different times during pregnancy.
Although there is no universally accepted definition of when a fetal death is called a stillbirth vs. a miscarriage, in the United States “stillbirth” refers to a fetal death that occurs after 20 weeks of completed gestation, and “miscarriage” usually refers to a fetal death that occurs at 20 weeks of completed gestation or earlier.
Stillbirth is more common than many people realize. Each year, about 25,000 infants are stillborn in the United States— almost 10 times the number of deaths that occur from SIDS.
Because of tremendous advances in medical technology over the last 30 years, prenatal care has improved, and the occurrence of late and term stillbirths has dropped dramatically. However, the rate of early stillbirth (fetal death occurring between 20 and 27 weeks of completed gestation) has remained essentially unchanged.
Common causes of fetal death include problems with the infant (birth defects or genetic abnormalities), problems with the placenta or umbilical cord, and certain conditions in the mother (e.g., uncontrolled diabetes, hypertension). (First Candle)
Overview of stillbirth
March of Dimes. Stillbirth. Quick reference: Fact sheet.
Overview of miscarriage