I just went to check on my ASF's and found my first litter!

There were 6 little babies, but unfortunately 3 of the 6 were DOA. They were about the same size as the live ones, but their faces didn't develop properly. (I can post some pictures if necessary)

What do you think the cause of this was? Bad genetics, first pregnancy issues, malnutrition, stress, something else?

Thanks for any input.