pubic region vs vagina

pubic region

noun
  • The central part of the (notably human) body near the pubes and the pubis, including the genitalia. 

vagina

noun
  • The vulva, or the vulva and the vaginal passage collectively. 

  • A similar part in some invertebrates. 

  • A sheathlike structure, such as the leaf of a grass that surrounds a stem. 

  • The passage leading from the opening of the vulva to the cervix of the uterus for copulation and childbirth in female mammals. 

  • A coward; a weakling; a pussy. 

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