When Adele, a new mother, visited my antenatal class and told them how she'd normally take paracetamol at the first sign of a headache but found labour pain quite different and do-able, the relief was palpable. "It is the most rewarding thing I have done. I knew every contraction was a step towards the finish line and ultimately meeting my baby, so I was able to chalk them off one by one," she says. Her joy and her plain-as-day enthusiasm about her son's birth was an instant antidote to the anxiety of the parents-to-be.

Women are more frightened of childbirth than they have ever been. Birth professionals know it, antenatal teachers like myself know it — and more recently the trend has been confirmed. The Association for Improvement in the Maternity Services (Aims) has acknowledged an unquestionable surge in women's birth anxiety in the past 20 years and, according to the Journal of Obstetric, Gynecologic & Neonatal Nursing, one in four women now currently suffer high levels of childbirth fear.

Although the rise in caesarean and instrumental births would seem to warrant this fear, it is not true that birth has become physiologically harder or that women's ability to labour has deteriorated. The steady rise in complicated birth – 39% of women needed some form of medical assistance in 2011 as opposed to 7% 60 years ago, according to BirthChoiceUK – is a result of increasing medical management and the fact the hospital environment can be a challenging place in which to labour normally.

With this increase in difficult births has come an inevitable rise in women's fear, creating a convoluted, self-perpetuating cycle: frightened women produce adrenalin, an antagonist of the hormone oxytocin, which fuels labour.

In the classes I run in Surrey, ordinary antenatal information cannot break the cycle. The Channel 4 series One Born Every Minute, opening as it does with a bone-chilling wail and a midwife running to an emergency, undermines a birth preparation class in a single episode. Breathing and relaxation exercises do little to unravel the damage caused by the scare stories women hear. A positive birth story can change all that.

Natalie Meddings, an active birth teacher in south-west London, and doula Kate Brown, realised the transforming effect of a positive birth story when they began informally matching pregnant women who needed moral support with new mothers.

"It evolved quite naturally. It was just a neighbourhood thing. When a woman came to me and said she was scared about labour I'd send her for a cup of tea with a new mum who could put it in perspective," says Meddings, 45, who is writing a book about childbirth fear.

Encouraged by the success, the pair sought to harness the power of positive birth stories and launched a more formal "birth buddy" national network in April – tellmeagoodbirthstory.com, a free and not-for-profit site. It has a growing database of mothers wanting to share their positive experience and wisdom. The emphasis is on human rather than virtual connections, with women meeting for tea or chatting on the phone.

"We have been overwhelmed by the scale of the response," says Brown, 33. In the first week more than 1,500 women visited the site and they already have a database of 150 buddies. "The response is an indication of the fear that's out there," says Meddings. "But also how eager women are to hear positive and encouraging messages about labour and birth. A woman's confidence in her body soars when she hears the simple message: "I did it, so can you."

One woman who was helped by a buddy is Sara Geneletti, from London. "When I was 15 weeks' pregnant I looked on YouTube for births and saw an episiotomy. I thought: 'I cannot possibly go through that.' I began looking into having a caesarean through health insurance." After further research into what would help her feel in control, Sara eventually decided to try for a home birth. But at the eleventh hour, her original fears reared their head and Meddings put her in touch with a new mother who birthed her baby at home.

"She was a sensible, normal person – I could see there was no special trick to how she'd managed. She'd just known what she needed. She restored my confidence without any persuasion at all." Sara went on to have her son at home, without intervention.

Helen Cleaves in New Malden has signed up as a buddy for four women. "I told them my story, nothing more," said Cleaves. "We emailed, texted, chatted. I was able to give them confidence and all four of them went on to have the births they wanted and were happy." She was motivated by her own experience. "When I found out I was pregnant I was pretty terrified. I did not know anyone who had had a good experience." She heard about births that went well at her yoga group. "When my waters broke I actually thought: 'Yes, bring it on.' I was looking forward to it and it was the most amazing experience of my life."

Mavis Kirkham, emeritus professor of midwifery at Sheffield Hallam University, is enthusiastic about the potential impact of positive birth stories: "A woman who has never heard an empowering birth story is unlikely to produce one. We tend to achieve our expectations around birth and positive stories help raise women's expectations."