Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you with today. I do apologize that your question was not answered before. Different experts come online at various times; I just came online, read about your wee one’s situation, and wanted to help.
When female birds lay eggs, it can take quite a toll on them. And if she is laying, this is non-productive (since she isn't producing chicks) and it would be best to take steps to help discourage Betty's body from thinking about laying .
Now since she currently has eggs in the cage, you do not want to remove them at this stage. When the eggs are removed right after laying, we usually end up with more being laid (which is not desirable since we are only stressing her body, not aiming to produce more babies). If we let her sit on them, this will usually "turn off" the ovaries and stop egg production. So, it would be worth letting her have them (or replacing them with wooden faux eggs) for at least a week after she has stopped laying.
Otherwise, I would note that there are a few environmental changes you can make to discourage her body from thinking about laying. The first thing to try is to consider cutting back her hours of light to no more than 10 hours a day, as we simulate winter (when birds shouldn’t be laying eggs). You can achieve this by covering the cage or keeping it in a quiet, dark room for the 14 hours of her ‘night.’ This will help modify her hormonal chemistry and discourage egg laying. Usually this is done for two weeks. If after the two weeks, you aren’t seeing an effect, then decrease the daily light exposure to 8 hours for a following two weeks.
Other options to deter laying include making dramatic changes to her cage to make her not want to continue laying eggs there. This includes removing any beds, mirrors, or toys (that she might be particularly attached to) and moving the remaining items around the cage. At this time, also remove any possible nesting materials and make sure there are no dark, warm cubbies to set up a new nest in.
Alternatively, you can even change her into an entirely different cage in a different room. Basically, the bigger the change, the more she will feel that now isn’t the time to be egg laying.
As well, just to note, we need to take care with handling at this stage. Specifically, we need to avoid petting Betty excessively on her back, stomach or under the wings. The reason is that this can actually stimulate ovarian production and potentially lead to more eggs. So, keep that in mind.
If you try the above and are still struggling, then it would be worth having her evaluated by her vet and considering hormone therapy at that stage. Your vet will be able to advise you if it comes to that.
Finally, if you have not already, I do want to note that you will want to make sure that Betty is getting adequate calcium supplementation. This is key because her body reserves can potentially be depleted by her egg laying.
So do try the above to retrain her brain to think it is winter and thus no time for egg laying. And if you are struggling at all, then you can find your local specialist avian vet, via the RCVS Register (HERE), http://www.aav.org/search/, or Avian web (LINK).
Please take care,