Research obtained by the BBC and the Bureau of Investigative Journalism reveals significant variation in adoption rates across England.
For children born in 2011-12 the chances of being placed for adoption by the age of five were 12 times higher in Southampton than Greenwich.
The data is from a series of Freedom of Information inquiries sent to all English local authorities. Half provided full responses.
Of those, 20 had significantly increased adoption rates for this group compared with children born five years before.
It is the first time groups of children have been tracked in this way over time.