I agree 100% with what has already been said, is this her 1st heat? if so Why are you breeding? she is far too young, if she is older than this have you had ALL the official health check for your breed done, and was she clear of any of these health problems, just because you have a bitch, is not a good reason for breeding, before you should even think of breeding you should at least research into what it entails, do you know you could possibly lose your bitch due to complications, she may need a ceasar operation (very costly) have you got homes vetted for the litter once they arrive?
There are more than enough litters being born from dogs with health problems, that end up in rescue all over. why would you possibly want to add to this number?
You have obviously NOT thought this through or done any research whatsoever, otherwise you would not have asked such a basic question. if you love your dog, do NOT go ahead with any breeding til she has proven she is worthy of breeding off and is old enough to do so. and please keep any entire males away from her at this moment in time. Help is always on hand here for someone who wishes to breed responsibly.
Mo