Hello, I'm Dr Gary. I've been practicing veterinary medicine since 2007. I look forward to helping with your questions/ concerns.
I would be very hesitant to breed a dog at this age. We usually don't recommend breeding a medium to large breed dog after 6 years of age. After 8, they are considered geriatric. There is going to be low fertility at this age, and a high chance of complications during and after whelping
. This would include the need for c-section, an increased chance of mortality at/ after whelping and a decreased chance of live healthy puppies.
We don't have pro-fertility drugs to use in dogs. There are options in mares, but not bitches. What you could do, is use Progesterone testing to time ovulation and then have an artificial insemination or in-vitro fertilization done to increase the chance of impregnation. You could do these with a vet that has a special interest in reproduction, or a specialist in the area (theriogenologist).
Here is a link to find a theriogenologist in your area:
I hope this helps, let me know if you have any other questions.