postpartum vs prenatal

postpartum

adj
  • Of a mother: after giving birth (often defined as within 30 days after childbirth). 

adv
  • After giving birth. 

noun
  • The period immediately following 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 postpartum and prenatal occurred in a corpus of books? (source: Google Ngram Viewer )