# Death

`````{admonition} Executive summary
:class: info

**Outcome:** Perinatal death

**Specific to HIE?**
* No 

**Which infants with HIE?**
* Most severe HIE

**Any other benefits or caveats not already mentioned?**
* Death is the outcome, but it is not an outcome that helps us distinguish anything - we'd need to know cause of death, and in that case, it's based on other information in the record, and not on whether or not they died.

**Conclusion:** Not recommended. Death is an outcome that can result from HIE - however, it doesn't help us identify whether or not an infant had HIE.
`````

## Causes of perinatal morality

The MBRRACE-UK Perinatal Mortality Surveillance Report on UK perinatal deaths for births in the UK in 2021 provides extensive information on the causes of perinatal death.

Causes of stillbirths:
* 33.2% placental causes
* 9.3% due to congenital anomalies
* 4.7% cord-related causes
* 4.5% due to infection
* 33.3% unknown cause

Causes of neonatal deaths:
* 32.6% due to congenital anomalies
* 14.2% due to extreme prematurity
* 14.0% due to neurological causes
* 9% due to cardio-respiratory causes
* 7.7% due to infection
* Neonatal deaths attributed to intrapartum causes remain low at 2.2% (a rate of 0.04 per 1,000 live births in 2021). However, an additional 11.1% of neonatal deaths of babies born from 32 weeks’ gestational age (0.18 per 1,000 live births) were attributed to Hypoxic Ischemic Encephalopathy (HIE), a type of brain injury caused by lack of oxygen to the baby’s brain around the time of birth.

[[MBRRACE-UK]](https://timms.le.ac.uk/mbrrace-uk-perinatal-mortality/surveillance/#causes-of-death)

## Association between HIE and death

Not all infants with HIE will die. In the US, the overall mortality rate of HIE is 15% to 25% with 40% to 50% of survivors developing long-term neurologic disabilities.[[Acun et al. 2022]](https://doi.org/10.1016/j.ajog.2022.06.002)