The biggest reason I know of for the size recomendations for female breeding size is how much producing the eggs/babys takes out of the snake.

A larger snake has more body weight and fat reserves that she can use. They also recover faster and regain weight after producing. Breeding a female that is just barly mature enough will produce a smaller clutch with babys that can be smaller as well. She will also probably produce less the following season as all the feedings will have gone mostly to recovery and less to overall growth.

If you wait for the female to get larger she will produce more and healthier offspring in the future.

There is also the chance that a small female may have diffuculty in passing eggs/babys and could become eggbound. As this can be deadly I would not take the risk.

Hope this helpes and best of luck with all your herps.

A
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1.0 BP Nicodemus
0.4 Cal Kings 3 alb 1 het Dora Queen Ace Pearl
2.0 Alb Corn Bizaar Elixir
0.0.1 Rev Alb Nelsons Oden?
0.0.1 toad Jabba