>>50973056Ditto copies things perfectly down to the genetic code and cell structure, so it would give birth like a normal human would.
But Ditto can't hold a form long enough for anything to happen, as the Dex entries say that things as simple as laughter, sleeping, or relaxing can cause it to change back to its base blob shape. Transform only copies 5pp of each move, so Ditto eventually runs out of energy and faints, reverting its form.
It probably can't stay in one form consistently for more than 1 day, let alone 9 months.