The 26-year-old former TOWIE star has kept fans updated along her pregnancy journey with regular snaps on Instagram.
But it seems she and footballer Andy, 24, wanted something a bit more special to remember her pregnancy by.
The couple stripped off for a stunning black and white photo shoot, showing a gorgeous Billi cradling her bump in one shot.
In another, she and Andy are looking at each other while he places a protective hand on her tummy.
Billi wrote: "4 weeks to go until we meet out baby boy @andytcarroll (another special moment captured by Maria Murray)"
It seems there's already a battle about what team Billi and Andy's baby boy will support.
Will it be dad Andy's current team West Ham, or his granddad's hometown of Newcastle?