para I vs primipara

para I and primipara both are nouns.

Word	Noun	Adjective	Verb	Adverb
para I	Yes	No	No	No
primipara	Yes	No	No	No

As nouns, para I and primipara are synonyms defined as:

para I and primipara: (obstetrics) woman who has been delivered of a child for the first time

para I (noun)	primipara (noun)
(obstetrics) woman who has been delivered of a child for the first time	(obstetrics) woman who has been delivered of a child for the first time