yes, if you have a good vet with the knowledge and experience to spay rats, get them spayed.
Spaying rats is important for health reasons
Why Spay or Neuter Rats?
Otherwise this will stop happening when the girls become elderly and no longer go into heat.
There are no special herbs, exercises, sounds/temperatures, training, de-conditioning, tricks or potions of any kind .... and please do not try any suggestions that do not come from a vet as they will not be safe
Rats are very smart and very motivated when girls are in heat (every 4 to 5 days) and people are not perfect 100% of the time. Having 2 intact sexes in the same home is an accident waiting to happen.
I have heard of rats that have gotten out of their cage in a basement rec room and gotten to the opposite sex in a third floor bedroom. I also know of experienced, very careful rat owners that have had accidental litters - if it can happen to them, it can happen to anyone.
Rats can have up to 26 babies in a litter, with average litter size being 12 to 14 babies … that is a lot of ratties to look after for the rest of their lives.
If intact boys are in the same home they will be affected when girls go into heat, it will impact their behaviour, and some may become aggressive because boys are hormonal too.