embryo vs lying-in

embryo

noun
  • In the reproductive cycle, the stage after the fertilization of the egg that precedes the development into a fetus. 

  • A rudimentary plant contained in the seed. 

  • In viviparous animals, the young animal's earliest stages in the mother's body 

  • The beginning; the first stage of anything. 

  • In humans, usually the cell growth up to the end of the seventh week in the mother's body 

  • An organism in the earlier stages of development before it emerges from the egg, or before metamorphosis. 

lying-in

noun
  • The final stages of pregnancy; accouchement. 

  • A period of postpartum confinement, typically a month or longer, formerly common in Europe and still practiced in some parts of the world. 

adj
  • of, or relating to childbirth or postpartum confinement 

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