give birth vs mass murder

give birth

verb
  • To become the parent of by birthing. 

  • To release live offspring from the body into the environment. 

  • To become the source of. 

mass murder

noun
  • The killing of a large number of people over a short period of time. 

How often have the words give birth and mass murder occurred in a corpus of books? (source: Google Ngram Viewer )