In ball pythons sexual maturity is usually reached at around 500g or a year with males......usually at a minimum.....and females at about 1300g more or less & 2 years of age.
So with that said....yes some balls can and will reproduce at smaller sizes, but does that mean its healthy? Probably not.....Granted people breed 1000g females but if you look at clutch sizes & weights youll notice that the babies are usually smaller and there are fewer eggs.
Why would you want to breed a small 1000g female that you know will probably only give you 3 or 4 eggs as opposed to a female that weighs 2500g after 2 years of good growing that can give you 8-10 eggs, and be able to regain weight after the breeding season and gain more weight for the next year. I dont know if breeding a small snake will stunt its growth or future production.....but it would make sense that it could defineatly stress the snakes reproductive system at such a young age..or even cause worse problems health wise.
JMO,
JAred Horenstein