A pregnant pause/silence
Definition 1 of 1
Pro Tip 1/3Expectation Building
Used when a speaker creates suspense or leads listeners to anticipate something important or surprising. 
He slowly opened the envelope, and during the pregnant pause, everyone held their breath.
Pro Tip 2/3Dramatic Effect
Emphasizes a dramatic moment or turning point in a conversation or event. 
The jury returned, and their pregnant silence was more unnerving than any words.
Pro Tip 3/3Emotional Weight
Indicates a moment is laden with emotion or profound meaning, often before a significant revelation. 
After a pregnant pause, she whispered, 'I'm leaving.'