Irina Shayk in Black Dress That Makes Her Look Pregnant

The answer is ... nothing -- although Irina Shayk's little black dress made it seem like she had something in the oven Thursday night in London.

Irina hit up Mark's Club in London with fellow model Lara Stone -- flashing max cleavage, but everyone's looking a little lower. Yeah, it kinda looked like she had a little extra in the belly area, and honestly ... we had to look closely more than twice.

But the dress is just a poor-fitting, optical illusion. Check out a side view of the supermodel 3 weeks ago.

We'll consider this confirmation, Bradley Cooper -- you're in the clear.