mischance vs stillbirth

mischance

noun
  • A mishap, an unlucky circumstance. 

  • Bad luck, misfortune. 

verb
  • To undergo (a misfortune); to suffer (something unfortunate). 

stillbirth

noun
  • The birth of a dead fetus; the delivery of an infant which is dead at birth. 

  • The birth of a dead fetus after 20 weeks of gestation. 

How often have the words mischance and stillbirth occurred in a corpus of books? (source: Google Ngram Viewer )