i recently had a bitch spayed and c/section at 60 days ,because we new she already had a weak womb (the mating was accidental),the vet wasnt happy there is a lot of blood loss ,therefore risks ,it is not reccomended and she was very poorly from the blood loss ,although all turned ok in the end ,have you found a vet who would actually santion this? my puppies are often born at 57 days quite healthy ,if you are serious !!!! there is a drug that is used for misaliance which will give a abortion even at this late stage .then spey the bitch when she has recovered