Responses

It depends. In some omegaverse, the womb is always there, just very small so when they go from beta to omega, the womb developed due to the alpha's pheromones, but it is still very small which is why it is harder for recessive omegas to give birth. In some omegaverse, it's pretty much pseudo omega where they experience the heat cycles but cannot give birth. In this story, the first one seems to be the case since he was afraid of getting preggo. Anyway, the short answer is, it's omegaverse, anything is possible should the author want it. o(〃^▽^〃)o
So he's a recessive omega that was a beta before does that mean he just grew a womb out of nowhere? Logically he shouldn't be able to get pregnant