I'm not an expert on adoption, but my impression was that in the UK it's very tightly controlled, for the sake of the child (as I said above). Adoption is not there nowadays for the parents. It's about finding exceptional parents for children who at a minimum have lost their biological parents and in many cases have many difficulties - behavioural and emotional issues, physical and mental health problems.
Adoption from outside the UK creates additional problems of uprooting the child from her/his own culture.
So yes, I'd have a big problem with a 64 year old, whether male or female, adopting a newborn child, but in the UK it just wouldn't happen (maybe unless it was a kinship adoption? others will know more than I do here).