Borst, a trained physician, was found dead in her garage Monday by a friend who called emergency services, DutchNews.nl reported.
While health minister for the Netherlands, Borst, 81, was responsible for shepherding legislation legalizing euthanasia and embryo research.
Dutch media earlier reported Borst had died under "suspicious circumstances," but Dutch public broadcaster Nos said later it wasn't the case.
"If it is unclear what killed someone, then there is always an investigation," police spokesman Thomas Aling told Nos.
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