When frogs mate they make babies then the female egg is fine, but her nucles is discard. While the man's egg is discard and his nucles goes inside her egg to make the tadpole (clone).
The enucleated egg and the transferred nucleus may not be compatible.
An egg with a newly transferred nucleus may not begin to divide or develop properly.
Implantation of the embryo into the surrogate mother might fail.
The pregnancy itself might fail
