
I am not sure but maybe when they are in heat the chances of their pregnancy increase, generally speaking from MOST manga I have read an omega's pregnancy is low its only when they are in HEAT that they have a higher chance at becoming pregnant.(⊙…⊙ )
Then again that is based off of what I have read while it is true Alphas have a very LOW chance at pregnancy I don't think that means they don't EVER get pregnant just the chances of it happening are very low. This is probably why most mangas use the alpha x omega dynamics instead of alpha x alpha. Σ(っ°Д °;)っ
Then again each author does things differently so although there are general tropes that are used in this genre that doesn't mean all authors follow a super strict guideline when writing it so if this story appears confusing that is another aspect to consider is maybe this author is doing things a little different. Σ(  ̄□ ̄||)(⊙…⊙ )
So yeah that is my perspective analysis on this story and the genre sorry if it came out like I was ridiculing or reprimanding you I can see how that would be confusing so I hoped my reply helped and wish you happy day or night wherever you may be and happy reading! (๑•ㅂ•)و✧ ╮( ̄▽ ̄)╭

In different Omegaverse there is different rules to who can become pregnant. There are 2 main worlds we read about. One is the traditional omegas are the only ones to get pregnant. The other is where other alphas can get pregnant. I believe in the first one male and females have dicks, and they can knot, however if you want to know I’m sure there is a translated omega verse rules page somewhere.
Just a general rule I go by is that beta males have about 10% of sperm active, Alphas have over 50, and Omegas are close to 0 if at all. Omega has a larger chance of getting pregnant in their fertility window than that of betas, however from my understanding female omegas are the most fertile.
Also noting that Alphas don’t have heats, they have “ruts” so they are very unlikely to get pregnant because their body isn’t prepared for pregnancy like omegas. I think in some worlds they use special drugs to increase the fertility of alphas but I’m not sure.

Yeah, since Omega is granted with a tragic destiny with the lowest privilege in the society so at least they should have some special abilities to balance with the mighty alpha and major beta. I was inclined with this kind of thought whenever reading Omegaverse. If not Omega is too miserable (︶︿︶)=凸

I think alphas can get married in general. Remember there are a lot of stories where the alpha family choose to wed their son to another alpha son/daughter. I think that the reproduction rate if it is alpha omega is higher than alpha/alpha or alpha/beta.
But it actually depends on the author. Omegaverse is an open concept so anything can happen

Maybe evolution found a way considering the low percentage of omegas. Alphas are pretty low too but not as much as omegas, as seen here. http://www.mangago.zone/read-manga/okusama_ha_alpha/uu/okusama_ha_alpha-chapter-1/7/ And since alphas in this story can get pregnant, it makes sense for upper class/pure bred alphas to marry each other to 'preserve' their genes considering how they're only 20% of the population. I also think there might be special drugs to increase fertility of alphas. It's the modern times and they're rich.
I'm confused. So a male alpha can conceive as well? Isn't Omegaverse is a world with premise that Omega has the highest reproduction rate while other genders like beta and alpha has very low chance of getting pregnant? If a male Alpha can easily conceive like this then what's the point of Omega?? This is quite unbalanced hmmm