"Surprise baby" adoption (i.e., agency is called to the hospital just after the baby was born)

Hello, has anyone adopted a domestic "surprise baby" (i.e., the agency is called to the hospital just after the baby is born, although the agency has never been contacted by the birthparents before)? If yes, how reliable was the medical history provided by the birthmother/birthparents? My understanding is that "surprise" birthparents also receive less counseling than those who go through a regular matching process. Did anyone have either good or bad experiences in this respect? "Surprise baby" is what our agency calls these situations, I'm sorry if this is the incorrect term. Thank you!