premature labour vs parturiency

premature labour and parturiency both are nouns.

Word	Noun	Adjective	Verb	Adverb
premature labour	Yes	No	No	No
parturiency	Yes	No	No	No

As nouns, parturiency is a hypernym of premature labour; that is, parturiency is a word with a broader meaning than premature labour:

premature labour: labor beginning prior to the 37th week of gestation
parturiency: concluding state of pregnancy; from the onset of contractions to the birth of a child

Other hypernyms of premature labour include childbed, confinement, labor, labour, lying-in, travail.

premature labour (noun)	parturiency (noun)
labor beginning prior to the 37th week of gestation	concluding state of pregnancy; from the onset of contractions to the birth of a child