Only if you're in a state without a putative father registry.
Seriously--that registry is SPECIFICALLY against paternal rights. She can come back ANY time in the child's life to get child support, but you have 30 days after the child is born to establish parental rights? Personally, I find that scary, but apparently I'm in a minority.
Really--this is exactly why you need a lawyer. Adoption law is VERY mucky, and changes so much from state to state it's not even funny. Step-parent adoption--same thing.
Either way, if the child has not been adopted yet, you need to establish paternity ASAP. If the child HAS been adopted, you're going to have to get this moving BEFORE they leave the country.
Call a lawyer TODAY.