due date vs full term

due date

noun
  • The date on which a pregnant woman is expected to give birth. 

  • The date by which a book (or other item) borrowed from a library must be returned. 

  • The date by which a task is supposed to be completed. 

  • The date of payment in financial arrangements. 

full term

noun
  • The period for which a pregnant woman carries a baby; the full nine months of gestation. 

How often have the words due date and full term occurred in a corpus of books? (source: Google Ngram Viewer )