fecund vs postnatal

fecund

adj
  • Highly fertile; able to produce offspring. 

  • Leading to new ideas or innovation. 

postnatal

adj
  • (of a mother) after giving birth 

  • after being born, of or pertaining to the period immediately after birth 

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