flash in the pan vs miscarriage

flash in the pan

noun
  • A transient occurrence with no long-term effect. 

  • A career notable for early success not followed by significant accomplishment. 

miscarriage

noun
  • The spontaneous natural termination of a pregnancy, especially before it is viable; the fatal expulsion of a foetus from the womb before term. 

  • A failure; a mistake or error. 

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