There's an interesting dichotomy between breeds. In breeds such as Mini Lops, where 9 babies is a norm, breeders want smaller litters. A litter of five grows better and faster than a larger litter. In smaller breeds, such as the Hollands, breeders want larger litters. In a litter of five, the kits are smaller and there is less of a chance of them getting stuck. 

As a result, I receive a lot of questions on how to make a litter bigger. I don't have the answer, but I have some theories that have been passed down to me from other breeders. I listed my thoughts next to the theories, but I also know multiple breeders that swear by the theories below. So don't listen to me--if it works for you, it works for you!

The Theories: 

1) Genetics: keep only the does that have large litters (keeping does that have more in their litters and weeding out the ones that had smaller litters. Of course, keep in mind that the buck's sperm count has a huge say in how may eggs are fertilized, it's not just the doe)

2) Breed only does with very wide hips just for breeding. (They don't have the stuck litters like the "show" does do.)

3) Breed only in the spring and summer. (Rabbits naturally have larger litters during that time of year)

4) Leave the doe in with the buck for several days. The thought is that she'll breed more often and have a bigger litter. (Honestly, the doe only drops eggs once, if she only drops 3-4 eggs, the more breeding isn't going to do anything...but I will go with the fact that there is more sperm, and thus more likely that all of the eggs will become fertilized)

5) Feed the doe less; causing the litter to be smaller. (I argue that the doe's body provides nutrition to the litter first no matter how much you feed, so you really just hurting the doe, but I know one breeder that swears this saved his herd, so I'm open to being wrong)

6) Increase the doe's exercise toward kindling. (I can agree to this one, it will essentially make her stronger allowing for an easier labor. There is some further research being done by actual scientists on this theory. In cats, dogs, horses and humans, they have found good findings, but have not released anything regarding rabbits yet)

7) Breed to bucks with smaller heads. (This is definitely a plus for the smaller does. Of course, if you're trying to show, this presents the problem that the standard calls for a very large head. The question posed to you then is how much do you want to chase the standard in exchange for your herd's health?)

8) Schedule c-sections. (This is one time ordeal. The scar tissue that builds up on the dwarf breeds precludes them from being bred again)

If any of these work for you--let us know. Have another one to add, please leave it in the comments.