Collocations for pregnant - adj.

be, look
When I found out I was pregnant, I didn't know what to do.

become, fall, get
get sb, make sb
He got her pregnant.

heavily, very
visibly
newly
She was newly pregnant at the time.

by
She was pregnant by a former client.

with
She was pregnant with twins.

six weeks, three months, etc. pregnant

Pregnant is used with these nouns:
belly, girlfriend, mother, mum, pause, silence, wife, woman