unborn child vs womb

unborn child

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

womb

noun
  • In female mammals, the organ in which the young are conceived and grow until birth; the uterus. 

  • Any cavity containing and enveloping anything. 

  • A place where something is made or formed. 

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