After the new birth certificate has been issued, no, she can not. The order of things is
1. exit PGN
2. birthmother signs the Protocolo - her fourth and final signature - and you are now legally the child's parents
3. ew birth certificate is requested and issued with you listed as parents.
Sometimes attorneys do have birthmother sign a POA at DNA or Family Court so they do not have to come back for the final signature. I have some issues with this being done (though my son's birthmother did sign one) but that is an issue for another thread.
