The country's top family judge has intervened in the case of a mentally-ill mother who had to deliver an unborn child by caesarean section by order of a court.
A local authority said the move was necessary because of concerns about "risks to mother and child".
The girl, now 15 months old, is being put up for adoption despite opposition from the mother, who is an Italian national.
Liberal Democrat MP John Hemming, who has taken up the mother's case, told ITV News he had spoken to her and "she would like to send a message of thanks to all the British people who have offered their message of support".
Political correspondent Carl Dinnen reports:
Earlier, Essex County Council issued a statement following reports that the child was "forcibly removed" from her mother by social workers.
It said that social services obtained an interim care order from Chelmsford county court in August 2012 "because the mother was too unwell to care for her child".
The mother was able to see her daughter on the day of birth and the following day.
She then went back to Italy, but later returned to Britain to seek the return of her daughter.
But a judge ruled in February this year that the girl should be placed for adoption because of the risk that the woman might suffer a relapse.
The council said: "The long-term safety and wellbeing of children is always Essex County Council's priority. Adoption is never considered until we have exhausted all other options and is never pursued lightly."
"Historically, the mother has two other children which she is unable to care for due to orders made by the Italian authorities.
"In accordance with Essex County Council's Social Services practice, social workers liaised extensively with the extended family before and after the birth of the baby, to establish if anyone could care for the child."