"Orgasm" and "childbirth" are not two words that sit well together in the same sentence. But as implausible as it may sound, increasing numbers of women are vouching for the notion of having an orgasm - even multiple orgasms - during birth. Labour, they claim, need not be an agonising ordeal - in fact, it can be as ecstatic and exciting as the moment of conception itself. While doctors caution it's an experience few women will know (and shouldn't pressure themselves to achieve), orgasmic birth has certainly caught the imagination. Two US documentaries depicting orgasmic births are set for release, and websites are awash with first-hand accounts from women claiming similar experiences.

Isobel Patterson, 31, a lawyer from Brighton, England, delivered her first baby, Amelia, during a home birth last December. She's convinced she experienced an orgasmic birth, witnessed by her husband, James.

"I'm aware that many women reading this will dismiss my experience as some sort of exhaustion-induced fantasy. Before it happened to me, I'd probably have done the same. Confessing to my friends - who have, in most cases, experienced painful 10- or 20-hour labours - that mine was the most enjoyable seven hours of my life, has been tough enough. But when I add that it included an orgasm, I find myself being made to feel in some way deluded.

"Like most mothers-to-be, I was terrified by the idea of giving birth. A typically pragmatic lawyer, I had decided on a hospital birth with every painkiller at my disposal, even before I became pregnant. I couldn't see the point in trying to go it alone when medical science could make the process easier.

"However, as my pregnancy progressed without any complications, my feelings changed. I began researching more natural, alternative methods. I engaged a doula. I loved the idea of a woman who would come to my home when I went into labour and was totally independent of the hospital, but experienced enough at delivering babies to help me through it. [Doulas, unlike midwives, don't assist in the actual delivery or provide medical care, but act as professional coaches who offer emotional and practical support during childbirth.]

"When my contractions started at midnight, it was my doula whom I called. I was a week overdue and wanted someone who wasn't emotionally involved with me. My mother and husband were sleeping, and I decided not to wake them up. I knew they would start panicking. But my doula was calm, relaxed and hugely positive about how wonderful the experience was going to be. I spent three hours on all fours in my living room before my husband and mother even woke up.

"As my contractions intensified and I got closer to giving birth, I remember starting to feel the sensations. It was the most incredible feeling that began in my pelvis and rippled through my entire lower body. It was wave upon wave of what can only be described as pure pleasure. My pelvis began pushing downwards involuntarily and my legs were trembling as I experienced a prolonged orgasm that lasted what seemed like hours, although during birth, your concept of time is very different.

"I know now that it was probably more like a series of orgasms over an hour. My husband said afterwards that I was shouting, 'Oh my God, it's so beautiful, it's like making love,' over and over again. I was trembling and smiling.

"The doula said my clitoris was pulsating and that I kept closing my eyes in ecstasy with each passing wave as the baby moved downwards. My husband just stood there open-mouthed. He didn't quite know what to say, although he said later it was obvious what was going on.

"My baby arrived, without any pain relief, three hours later, and my recovery was incredibly quick because I didn't tear or need stitches. I felt wonderful, but was slightly confused and embarrassed about what I had experienced. I also felt guilty that I had felt something usually associated with sexual intercourse during the birth of my daughter. But when I went online, I found hundreds of women blogging about similar experiences.

"After the birth, I was so excited that I wanted to share what had happened with friends, but their reactions quickly taught me that this was probably something I should keep to myself. It's sad that women are too embarrassed to talk openly about orgasmic birth, but hopefully, in the near future, we'll be more open-minded about our sexuality."

For the expert's take on orgasms during delivery, read the July issue of marie claire.