ovule vs unborn child

ovule

noun
  • An immature ovum in mammals. 

  • The structure in a plant that develops into a seed after fertilization; the megasporangium of a seed plant with its enclosing integuments. 

unborn child

noun
  • A human offspring that is developing in the uterus; fetus. 

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