Imagine Barry and Oliver finding out that Barry is pregnant...with HIS TWINS. They find out when Barry gets nauseus after mission and Cisco is so excited but Catlin is like " I don't want to know why you didn't use protection."

Ok, but, right - here’s the thing. (And I’m assuming this is A/B/O so I’m going with it)

There is NO CHANCE IN HELL that Oliver is letting his pregnant Omega out of his sights for even a second. Oliver would wake up next to Barry and smell the pregnancy instantly, and I can see him being the most over-protective Alpha on the planet and refusing to let him even leave the apartment, never mind go out on missions.

So I feel that Oliver would make sure that everyone knows not to let him, because Barry can be as stubborn as he is sometimes, and he’s pretty sure that he’d sneak out otherwise. 

(I don’t see him being a controlling asshole about it, though - he merely wants to protect Barry and the lives growing inside him)