Hi, this is Dr. Maggie - I am going to try to answer your question today.
How old is the male that you are planning on breeding your female to?
If it is the size of the female that you are worried about, it sounds like you are choosing an appropriately sized male to breed her to. However, any time you breed a female that is that small there is an increased risk of dystocia (difficulty giving birth). So you will want to be very careful in watching her around her due date.
A good resource that I like my clients to visit (if they haven't raised puppies before) is the following link:
This link has lots of excellent information and even provides a video of a live birth for clients to watch.
Other things to keep in mind, make sure both of your dogs are up to date on all their vaccinations prior to breeding (especially your female as you can't vaccinate her for anything other than Rabies while she is pregnant).
Also, I always recommend getting any dogs you are intending to breed tested for Brucellosis prior to breeding.
This is a simple blood test that can be done at your local vet clinic to make sure both the male and female dogs are negative for B. canis (which is a disease that can cause abortion in dogs and if puppies are born with it can be harmful to humans).
Any other questions I can help you with today?
Also, I always recommend heading to your vet about 2 weeks prior to the anticipated due date for either an ultrasound or x-ray to determine how many puppies you should expect. (So you can count them as are delivered).
Yes, I think the size should be just fine. (As long as you watch the female carefully.)
Any other questions I can help you with?
As I mentioned ANY time you breed very tiny dogs there is an increased risk, however I have seen many very small dogs bred to other small dogs that had normal deliveries.
If you found this information helpful, please rate this answer positively so I can get compensated for my time. Please let me know if you have any other questions and I will be happy to elaborate further.
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