co-father vs procreator

co-father

noun
  • In a male homosexual couple, the nonbiological father (partner of the biological father) of a child. 

procreator

noun
  • One who procreates; a father or mother. 

  • One who originates or creates something. 

How often have the words co-father and procreator occurred in a corpus of books? (source: Google Ngram Viewer )