post-partum vs prenatal

post-partum

adj

  • Pertaining to the period immediately after childbirth. 

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. 

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