Hi and welcome to YT
.
For me, it's more of a very concerning question bc whelping can literally (and very easily!) be a life and death situation for both Mom and puppies. So, I'd be super concerned about that many puppies. I personally could not let one of my babies go through a birth; couldn't risk it, they're just too beloved. For me, breeding is best left to the true experts and those who breed for the betterment of yorkies.
Do you have breeding experience, btw? If not, you have a ton of learning ahead of you and I'd most def see if there is a mentor who can get you through the birth.