miscarriage vs stillbirth

miscarriage and stillbirth both are nouns.

Word	Noun	Adjective	Verb	Adverb
miscarriage	Yes	No	No	No
stillbirth	Yes	No	No	No

As nouns, miscarriage and stillbirth are synonyms defined as:

miscarriage and stillbirth: a natural loss of the products of conception

Other synonyms of miscarriage include spontaneous abortion.

miscarriage (noun)	stillbirth (noun)
a natural loss of the products of conception	a natural loss of the products of conception
failure of a plan