vaginal birth vs parturition

vaginal birth and parturition both are nouns.

Word	Noun	Adjective	Verb	Adverb
vaginal birth	Yes	No	No	No
parturition	Yes	No	No	No

As nouns, parturition is a hypernym of vaginal birth; that is, parturition is a word with a broader meaning than vaginal birth:

vaginal birth: the parturition process in human beings; having a baby; the process of giving birth to a child
parturition: the process of giving birth

Other hypernyms of vaginal birth include birth, birthing, giving birth.

vaginal birth (noun)	parturition (noun)
the parturition process in human beings; having a baby; the process of giving birth to a child	the process of giving birth