prenatal vs prepartum

prenatal

adj
  • Being or happening before birth. 

noun
  • A dietary supplement to be taken by somebody expecting to give birth. 

  • A person who is expecting to give birth. 

prepartum

adj
  • Before giving birth; prenatal. 

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