The HSE does not know how many investigations into almost 500 baby deaths and birth-related brain injuries over the past four years led to negative outcomes.
This is despite there being 488 cases where a baby was either stillborn, died within a month of birth, or suffered brain dysfunction being reported to the HSE as a so-called Serious Reportable Event.
Aked what proportion of probes resulted in a negative finding, the HSE said the information is held locally in each hospital and not collated centrally on any HSE system.