live birth vs birth

live birth and birth both are nouns.

Word	Noun	Adjective	Verb	Adverb
live birth	Yes	No	No	No
birth	Yes	No	Yes	No

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

live birth: the birth of a living fetus (regardless of the length of gestation)
birth: the event of being born

Other hypernyms of live birth include nascence, nascency, nativity.

live birth (noun)	birth (noun)
the birth of a living fetus (regardless of the length of gestation)	the event of being born
	a baby born; an offspring
	the process of giving birth
	the kinship relation of an offspring to the parents
	the time when something begins (especially life)

live birth (verb)	birth (verb)
	cause to be born