They have to have thier first heat usally around 6-9 months but It would be best to wait until she has her second heat to breed her. Good Luck. Hope this helps.
How Old Does A Puppy Have To Be To Get Pregnant?
They can get pregnant in there first heat ( around 6 months old) but do not breed them until there second heat ( around 1 yr old). There bodies are still very immature. Some don't make good moms there first go around.