No other language I know uses a word to pregnantclose to ours (Portuguese), but Norwegian does? Fascinating! Pregnant, Schwanger, even Spanish has embarazada, but in portuguese gravid = grávida :0
It's from the Latin "gravis", which means "heavy" (among other things). You'll find a parallel in the English expression "to be heavy with child".
Yeah, gravid is used in English to refer to late pregnancy but not often in casual conversation. I think it's more often used as a literary device.
In English medical terms, "gravida" refers to the number of times a woman has been pregnant.