fetal vs paternal

fetal

adj
  • Pertaining to, or connected with, a fetus. 

paternal

adj
  • Of or pertaining to one's father, his genes, his relatives, or his side of a family. 

  • Fatherly; behaving as or characteristic of a father. 

  • Received or inherited from one's father. 

  • Acting as a father. 

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