Sophia Mackintosh is all too aware that she is a walking stereotype. After two miscarriages and a failed IVF attempt, she decided to give up trying for a baby and buy a dog instead. With Lulu happily installed in their newly renovated house in Islington, North London, Mackintosh and her husband, James, launched themselves wholeheartedly into the adoption process. Then, five years after that first traumatic miscarriage, she discovered that she was pregnant.

Hers is a familiar story of the type gleefully recounted by those who believe that women today try too hard to get pregnant. Mackintosh agrees - she believes that during those five years her mind was sabotaging her chances. “I became obsessed. Every month I would pee on an awful lot of sticks and be disappointed each time that I was not pregnant,” she says. “But, deep down, there was relief that at least I would not spend the next 12 weeks panicking about having another miscarriage.”

After beginning the adoption process, Mackintosh, a charity director, began seeing a fertility counsellor. “I began to see my body in a positive way again, and she taught me to be calmer about life and confident that I would have a baby one day. And because we were about to adopt, James and I weren't trying quite so desperately to conceive.” After the fifth session, she was pregnant, and now, at the age of 40, she has two sons, aged 3 and 1 (plus Lulu the dog).

Mackintosh's story is one of 15 collected by Michaela Ryan for a book, Trying to Conceive (Vermilion, £10.99).

The idea that the mind has a large part to play in fertility is also advocated by the midwife Zita West, who last month launched a Manage Your Mind programme at her London clinic. Each hour-long session costs £110 and a course of one to six sessions is recommended. Techniques include guided relaxation, art therapy, hypnotherapy and cognitive behaviour therapy (turning negative thoughts into positive ones).

West says: “I know it makes me sound woolly, which I most certainly am not, but I have been doing this for a long time and I'm convinced that the mind-body link is crucial.” She says that “unexplained infertility” accounts for up to 23per cent of infertility cases, and 80 per cent of these could be down to the mind. The cause could be a subconscious fear of having a baby or the stress that comes from worrying about being unable to conceive. “Negative messages from the past are very important; they stay with you.”

Although evidence for “mindset infertility” is scant, there is a growing acceptance that stress can affect the part of the brain governing reproductive hormones. “Basically, when an animal is stressed, it sends signals to suppress reproduction,” says Dr Jacky Boivin, a Cardiff University psychologist who specialises in infertility. “This has been proved in rats, sheep, cows and bulls, but in humans it's more difficult to prove.”

The Boston obstetrician Dr Alice Domar, a pioneer of the mind-body connection, has carried out several studies. In one, she recruited 185 IVF patients; a third did her ten-week mind-body programme, a third joined a support group and the remaining third had no extra support. She found that 55per cent of the mind-body group , 54 per cent of the support group and 20 per cent of the control group conceived.

Seeta Rashid was 28 when she and husband, Tahir, began trying for a baby. After a year nothing had happened and medical investigations proved inconclusive, so the couple joined the estimated 400,000 people in Britain with “unexplained infertility”. After three failed attempts at intrauterine insemination (IUI), where the sperm is injected into the uterus, Rashid joined Cradle, a local support group in Renfrewshire. “Infertility consumes you; it puts your life on hold. Every time you go out, all you see are pregnant women or women pushing prams. You think everyone in the world is pregnant except you,” she says. At Cradle she learnt relaxation, changed her diet, took up yoga and studied techniques to challenge negative thinking.

Soon after, she began her fourth IUI, which succeeded, and the couple's daughter, Hema, was born in September, 2005. While on maternity leave, Rashid and a fellow Cradle member, the geneticist Sam MacCuish, persuaded Domar to visit Scotland. The pair secured Lottery funding and were trained in Domar's ten-session mind-body programme. They have run one pilot and one “proper” course, each for six IVF couples who had previous miscarriages and/or failed treatments. From the second programme, five of the women got pregnant, and the sixth decided not to go ahead with treatment - an 83 per cent success rate.

While running the course, Rashid put the ideas into practice, and naturally conceived her son, Gibran, who celebrated his first birthday last weekend. “I can't say for certain what made the difference, but the mind is a very powerful thing and we should never underestimate it.”

Many doctors remain sceptical, however. “Just look at some of the stressful states that people have lived in - the Second World War, starvation in Africa - yet women still conceived easily,” says Richard Kennedy, a fertility specialist at University Hospital Coventry and secretary-general of the International Federation of Fertility Societies.

He won't dismiss a mind-body link completely, however. “You hear of couples who get to the point where their doctor says that there is nothing more that can be done, so they decide to get a dog or spend their money on a world cruise. They relax - then they get pregnant naturally. But to my knowledge there is no research on that link.”

British Infertility Counselling Association (www.bica.net)

Cradle (www.assistedconception.org/cradle)

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