'when you don't want it you just dread every physical change, you feel out of control ... invaded'

Christine remembers how she felt when she discovered she was pregnant seven years ago. "Terrified. Absolutely terrified. At first I just pretended the whole thing wasn't happening. Eventually I bought a pregnancy kit, but I just didn't dare use it. I couldn't face knowing." Christine was 21 and unmarried.

"I had absolutely no idea where to get any help, or what my options were. My boyfriend told me if I kept the baby it would shame his family; my stepfather wasn't keen on the idea of a mixed race child and I was told I couldn't live at home. I was completely confused. But I decided to go through with it. Alice is six now and I still have to cope alone. There have been times when I've regretted taking on the responsibility - sometimes I feel I can't offer Alice enough and wonder if I've done the right thing. I certainly wouldn't wish my own experience on anybody."

It is perhaps not very surprising that Christine feels the way she does. She faced a life-altering event utterly unprepared for the physical and emotional consequences. Her trauma will echo with any woman who has found herself pregnant without wanting to be. Yet in all the current furore surrounding abortion, as the opinion formers attempt to fight their way out of the moral maze, practically no attention has been paid to the ordeal of coping with a pregnancy that's unexpected.

Under the 1967 Abortion Act, a woman can obtain a termination if two doctors feel that continuing the pregnancy would be damaging to her physical and mental health. What's provoking debate is how these conditions are interpreted and whether abortion is too readily available as a result. More fuel was added to the fire last week as one (unnamed) gynaecologist defended his practice of giving abortion on demand, while another complained: "A woman phoned me because her pregnancy clashed with her holiday

Some commentators are also taking a more cautious line. Angela Lambert wrote in the Daily Mail: "Today, many people are re-thinking their position on abortion ... they concede that we dismissed too casually the viability of the foetus, or the capacity of a woman ... to adjust her life to accommodate that of a child she may not have planned." Last year the writer Naomi Wolf expressed similar sentiments when she described how her own pregnancy had suddenly made her previous pro-choice stance too simplistic.

Perhaps motherhood has influenced this highly vocal generation of baby- boomers who were once so strident. Ann Furedi, director of the Birth Control Trust, finds the change alarming. "We're seeing a complete turnaround from the 1970s," she says.

"All the discussion at the moment is looking at unplanned pregnancy from the point of view of the foetus - rather than trying to understand the consequences the event can have on the life of a woman."

This reflects a shift in focus from a woman's rights to her responsibilities - where the mother's experience is viewed as a secondary consideration. "A lot of people seem to imagine that when a woman is pregnant she goes into suspended animation for a few months," says Furedi. "But if a pregnancy is unplanned, the shock of that positive pregnancy test - and the incredible realisation of how it may change your life - can be devastating. Women feel they're on a conveyor belt which speeds up and propels them into a situation they feel they have no control over."

Christine also found it extremely isolating. "I had to leave home and move in with a stranger. I refused to attend any ante-natal classes because I couldn't bear to be near women who had partners," she says. "I felt people were judging me, which I found highly hypocritical - if you have a baby on your own it's seen as irresponsible but if you choose abortion you're selfish too. You can't win."

This sense of injustice can continue once the child is born. Sue Wright, a professional line advice manager for Exploring Parenthood, the national parents' counselling service, often discovers that an unplanned pregnancy is at the root of problem relationship between mother and child. "It has an enormous impact, especially if the child is difficult. It she never wanted it, she resents it more," she says. "It seems like an unfair punishment for something she has given up a great deal for. It's like, 'I've done this for you and you must give back what I need.' Because of that there's a great deal of guilt which becomes part of the interaction with the child."

There are also psychological factors during the pregnancy itself. "Some women feel the unborn child is taking them over; sapping all their strength and undermining their body," says Wright. "It has a lot to do with the ambivalence that they feel." It's this ambivalence that creates emotional stress. Jenny, 32, had an abortion five years ago and was surprised by her response to the event. "I was in a steady relationship with a well- paid job but the idea of being pregnant appalled me - there was no way I was ready for it. In that first half-hour when the test showed positive I felt this rush of excitement like, 'My body works - I know I'm fertile.' Then I went through a chain of thoughts: 'Can I have it? What are my reasons for not having it?' After counselling I opted for abortion. I had to wait for three weeks during which time I got terrible morning sickness and my breasts ached. I kept thinking, this must be amazing if you want to be pregnant - but when you don't, you dread each physical change taking place. I felt a complete loss of control; that I was being invaded. Straight after the abortion I felt a tremendous sense of relief that this 'thing' was out of my body."

It's hard to imagine how traumatising it would be to continue a pregnancy in this frame of mind, although that would have been unavoidable less than 30 years ago. When Sonia discovered she was pregnant in the 1960s aged 18 the sole choice was adoption - an option now favoured by pro- life campaigners. For two-thirds of her pregnancy, Sonia lived in a mother and baby home waiting to give birth. "If I could have found a back street abortion I think I would have taken it. I felt my body had been taken over and that my role was that of an incubator on behalf of better people than me. I began to hate myself more and more.

"Giving up the baby after being with him for six weeks was like going through something as traumatic as death except you weren't allowed to talk about it," she says. "People who say they're anti-abortion talk about adoption so lightly. They don't know the life-time repercussions of giving away your own child. It's a burden no one should be expected to carry."

According to Dr Lorraine Sherr, psychologist and author of The Psychology of Pregnancy and Childbirth, it's this sense of conflict that is so distressing to a pregnant mother. "One study has shown that unwanted pregnancy does increase anxiety and depression in both mother and father," she says. "And we know that forcing a woman to go through pregnancy will have not only a damaging effect on the mother but on the child too. We also know that pressure or coercion, whichever way, is the worst predictor for mental health problems; it's when she feels pushed or pressurised, wanting one thing but doing another."

This is because the actual process of trying to make the right choice can be so traumatic, says Sue Germain, a counsellor for the Brook Advisory Centre. "Often women are in a state of shock, they can't think clearly. They veer from wanting it to not wanting it and feel they'll never be able to reach a clear decision. It's a huge decision for every woman I see - they are never flippant about it, whatever stage of pregnancy they are at. Once they have made up their minds, it's often the worst part over."

Yet Canadian psychiatrist Philip Ney believes that, on the contrary, a woman's psychological well-being is under threat when she opts for termination. "She's denying the crisis of pregnancy by saying, 'I will not change', 'I cannot accommodate or expand'," he says. "Abortion is so difficult because a woman knows she is carrying something around that will never live - that's the most difficult grief of all."

This is what happens, the critics seem to be saying, when women are spoilt for choice: they abuse their freedom. Yet listening to Sonia, it's easy to forget how recently there was no choice at all. She is quite clear about her abiding memory of pregnancy. "It was the terrible feeling of being trapped. You had so little power; there were no options available and there was nothing you could do personally to change events. I can't forget. It was a nightmare."