The Man posted an ultrasound of The Baby (nickname pending) in honor of her fiance's birthday on Thursday ... saying "I love you and can’t wait to start this next crazy chapter with you."

Still no word on gender, name or exact due date -- but hey, at least we got a pic!

Of course, the wrestling community went wild earlier this month when Lynch announced she was relinquishing her Raw Championship belt to start a family with the fellow WWE Superstar.

The couple found out a little one was on the way back in April ... and Lynch has recently said she's always wanted kids.

Lynch posted an emotional message to the papa-to-be on his 34th cake day ... saying, "This person right here is my favorite person in the world."

"I thought I was doing fairly well in life before, but then you came along and made me feel like the luckiest (and happiest) human in the world."

Lynch and Rollins have been dating since early 2019 ... and got engaged in August during a romantic beachfront proposal.

Can we just take a second to appreciate how attractive this couple is??