English to Spanish Law/Patents Certificates, Diplomas, Licenses, CVs UK Birth Certificate

This is a difficult one (or I'm getting drowned in a glass of water!!)

At the end of this birth certificate from the UK, below the point "17. Name given atfter registration and surname" which is crossed (i.e. no name) and outside the box, it says in handwritting:

"Adopted J XX Deputy Superintendent Registrar"

I have done hundreds of these certificates but it's the first time I encounter this and can't find out what they are referring to with "adopted"...
Everywhere I looked it gives the translation as "adoptado", but it doesn't seem right in this case...

The certificate has all the details of the child and the mother (no details of the father), and there is no mention to an adoption by anyone.

Any ideas?? I'm lost!
GRACIAS!!!
Grace.