![](https://pic1.mangapicgallery.com/r/avatar/72/u130346_50x50.jpg?2)
This is just my speculations from the various ABO mangas and novels that i read...
I think it's about the fertility rate of each type, like the omega has more chance at getting pregnant than the other two,
while the beta has a lower chance of pregnancy than the omega, but they have a higher chance than alphas,
And the alphas has the lowest chance of getting pregnant, since their biological setting is for them to be the dominant one but it's still possible to give birth, it's just a lot harder for them to do...
![](https://pic1.mangapicgallery.com/r/avatar/1b/u88533_50x50.jpg?2)
http://www.mangago.zone/read-manga/falling_alpha_enigma_the_fourth_bath/ You might mean this (but it's alpha-->omega)
Tell me one thing ( ̄へ ̄)
In Omega universe, we know all omega can give birth but we also have seen male alpha can also give birth (in few story). In short accept Male beta, everyone can give birth.
Don't you think the population of the world will increase really fast?? ┑( ̄Д  ̄)┍