I would say definitely not a good idea - have just had a horrific experience with a friends bitch who was 6 - it was not her first litter, and previously she whelped like 'shelling peas - cut a long story short she couldnt get the puppies out, had to be rushed to the vets, and out of a litter of 4, she lost 3 - we are presently hand rearing the remaining puppy with feeds every two hours as the mom's milk has dried up.
It is definitely rather late for her to have a first litter, but if she has whelped a litter before then she should be ok, provided she is in good health and has had all necessary health checks for the breed. The Kennel Club have a rule that puppies from bitches over 8 years old cannot be registered.
No it would be dangerous, particularly if her first litter .
very unfair to even consider this IMHO also, what are your reasons for breeding ?
If your bitch and sire are not health tested and perfect examples of the breed (ie proven show winners) and you do not have homes waiting for the pups before they are even conceived then you are not a reputable breeder. You also need to provide full back up for the new owners in case they have problems and be prepared to take the pup back.Think of the many abandoned unwanted pups and dogs in rescue centres ?? Also do you realise the amount of time and energy that goes into caring for a bitch and her pups not to mention the cost, from before conception until at least 8 weeks after their birth ?
Reputable breeders do not breed for the money ! but to improve the breed !