how old is molly??
how many times has she been breed? did you skip a heat? inbetween litters?
we give ester c as a suppliment
also you have to stay calm,,,,,the bitch knows how you feel.pet her, tell her she is doing great etc.
her temp will drop 3 days before whelp. are you using the same stud??
he might have a low sperm count, ie; small litter
also we put them on bayatrill , a pregnant safe antibiotic before breeding and into the 1st trimester, if any kind of infection is around it will kill the infection that might pass to the puppies.
good luck, stay calm,,,,,,,molly will know what to do, just stay with her and have a vet on call, just in case.