all that gets added to the original entry is the word 'adopted' in the right hand column and a new registration takes place in the new name, for the adopted child the process for getting the original birth certificate is applied for on form CAS 5/6 and that will also give you info on which court authorised the adoption and you get another form to submit to the court asking for details on which adoption agency or local authority handled the case. they can also apply for a 'guardian ad litem' report which is the report made at the time. that file is important to get at because it may contain an awful l,ot of info on the child and birth family. so actually yes, with persistence and filling in the right forms the adopted child once over 18 can find out what they need to. They should be on the contact register for blood relatives first though.