Leave the country, until the child is grown.............
It wouldn't matter. Virtually every country in the world is a signatory to Hague and UN treaties against child-stealing. Wherever this woman goes (irrespective if that country does or does not have a formal extradition treaty with the US), with very few exceptions, she would be arrested, and even if she wouldn't be extradited back to the US, the child would be returned to the US.
These treaties were the foundation for the argument that eventually prevailed to return the US child in Brazil back to his New Jersey father.