Looking at 15-year-old Katie Thorpe in her wheelchair, a child-like smile on her face and dribble on her chin, it's easy to see why her mother is convinced that pregnancy is out of the question for her. Did you see the TV news film of her? Katie was at a go-kart race but as the machines whizzed past it was hard to tell if she knew where she was. Katie suffers from cerebral palsy.

Her mother, Alison, was alert enough for both of them. She bobbed up and down, talking into her daughter's ear, investing her voice with enthusiasm, while mopping the girl's chin. Alison and Katie have been dragged from the obscurity of their everyday lives into the media glare because Alison has asked surgeons to remove her daughter's womb. If they consent it will be a first for Britain. It is understood that doctors are researching the legal position. Meanwhile, disability rights groups are horrified.

To them - and to all who would judge her - Alison Thorpe says: "Come and spend a week with me. Walk in my shoes."

She has spent 15 years, day in and day out, being Katie's carer. She says she loves her daughter dearly, and who can doubt it? She says she is trying to do her best for the girl and that this operation is right for her. "Katie will not have a normal life," her mother says. "She will not get married and have children. Why, then, should she suffer the mood swings and discomfort of menstruation? She won't understand it and it will distress her."

Alison Thorpe comes across as a practical person; a problem solver. She sees a situation approaching that neither she nor her daughter can easily cope with, and she has identified surgery as a quick and efficient solution. "It might not be the right thing for other children with cerebral palsy," she says, "and I'm not advocating that every disabled girl should have a hysterectomy, but the choice should be there."

The question for society is: "Should it? And should it be there at a mother's request?"

Let me quote you a short passage from a novel I read some years ago. It is called Under the Eye of the Clock by Christopher Nolan: "Paralysed I am labelled but can a paralytic move? My body rarely stops moving. My arms wage constant battle, trying to make me look a fool. My smile, which can be most unnatural, can at times freeze, thereby making me seem sad and uninterested. Two great legs I have but put my bodyweight on them and they collapse under me like a house of cards."

Nolan, too, suffered from cerebral palsy. He couldn't speak and was, as he says, a mass of jerks, twitches and lunges. The world thought him an idiot until his mother strapped a prod to his forehead so that he could type. Even then it took a drug that quelled his tremors before he could hit the keys. His writing is poetic, perceptive and poignant.

Christy Brown was also condemned by cerebral palsy to life in a wheelchair. You might recall Daniel Day Lewis playing him in the film of his life, My Left Foot, the only part of his anatomy he could control. Brown followed that book with Down All the Days and A Shadow on Summer. Significantly, when thinking about Katie, he also married.

It is clear from these two examples alone that people who suffer from cerebral palsy cannot be judged by their appearance. I am not saying literary talent is necessarily a consequence of the condition, merely that the condition does not preclude it. It is clearly possible to be rendered physically helpless, while being mentally and emotionally intact.

Nolan and Brown, one mute, the other almost verbally unintelligible, managed to communicate. How many sufferers are there who haven't found a way to speak for themselves? The able-bodied are too quick to judge by appearances, as charities for the disabled have been pointing out. A spokesman for the UK's Disabled People's Council said: "Katie, like any other non-disabled teenager, has the right to grow up with her body intact, and where she has the same choice as anyone else to give birth to her own children."

But what if Katie simply doesn't have the capability to make that choice? It is significant that in the case of both Nolan and Brown, the person who spotted the hidden talent, the person who has acted as their interface with the world, was their mother. As is almost inevitably the case with a disabled child, the mother is the chief carer. It is she who lifts and lays and wipes and cleans and nurtures and cares for the child, until the two are almost one - like Alison Thorpe and Katie. I would be romanticising motherhood and minimising the gruelling nature of on-going care to suggest that all mothers are as devoted. But there is no doubt about Alison's good intentions.

She knows her daughter better than anyone and she says Katie won't understand or be able to cope with the changes puberty brings. She is looking ahead to decades of monthly mood swings, cramps, discomfort and mess that she says will bewilder her daughter - and for what? If, on the inside, Katie was intellectually sound and emotional mature, this mother would be saying so. She would be fighting like she is now, but she would be fighting for education and social outlets for her girl.

Her mother has ruled out less permanent solutions such as implants and pills because she fears they could cause thrombosis. Surgery is quick, foolproof and efficient.

Critics say a hysterectomy is a surgical solution to a social problem. They say society should adapt to accommodate disabled children, instead of children being modified to accommodate society. Fine words, Alison Thorpe will say, but it is she and not society who will end up having to cope.

Her point is that if Katie is denied the operation she still won't have babies; just monthly distress and confusion. She might be right but it is conjecture. Menstruation can be many things. It can cause mood swings and pain. It can also be light, short and effortless. Before any radical solutions are sought, the reality for Katie should be observed and assessed. A hysterectomy can always happen next week, next year. It can't be reversed.

That said, like so many carers, Alison Thorpe doesn't get much from society. She has coped for 15 years and the likelihood is that she will carry on coping long after she and Katie have faded from our memories. If this one request is granted, it could ensure her life doesn't get harder than it now is.

She isn't asking for surgery for every disabled child; she isn't trying to set a precedent. Her message is simply that brain damage has robbed Katie of the ability to form a romantic or sexual relationship and to care for any child that resulted from it. She wants Katie's body brought into line with that harsh reality. My inclination is to accept this mother's word about her daughter: to grant her wish. But if the courts agree, they must emphasise that it is a solution for one child with cerebral palsy, certainly not for all.