Mencap has greeted a landmark high court decision as a victory in preserving the rights of people with learning difficulties against invasive medical treatment.

Dame Elizabeth Butler-Sloss, president of the High Court Family Division, overturned a high court ruling in January to impose a hysterectomy on a 29-year-old woman with severe learning difficulties. The woman's mother sought court backing for the treatment in a bid to protect her daughter from pregnancy.

But official solicitor Laurence Oates, acting for the daughter, lodged an appeal against the decision.

Mencap head of campaigns Richard Kramer said the judgement was clearly in the best interests of the daughter.

"The sterilisation issue raises particularly sensitive and moral questions," Kramer said.

"But sterilisation cannot be in a person's best interest if based on social, rather than health grounds."

The high court was told that the daughter had a mental age of six and would not be able to cope with pregnancy or parenthood. She is expected to move to sheltered accommodation in future and her mother is concerned that she would be at risk of being "taken advantage of" and becoming pregnant.

Dame Butler-Sloss said she sympathised with the woman's mother, but ruled that a hysterectomy would be "out of proportion, at this stage, to the problem to be solved".

The daughter has the right "not to have drastic surgery imposed on her unless or until it has been demonstrated that it is in her best interest", Dame Butler-Sloss said. Instead a contraceptive coil will be fitted.

Kramer said the judgement was clearly in the best interests of the daughter. "Her rights are paramount," he added.