My pregnancy was developing nicely. I felt queasy, but nothing out of the ordinary. When I was pregnant with my son, Buzz, two years' earlier, I had felt so alienated and stressed whenever I came into contact with the medical profession that I decided not to involve the NHS again. I didn't have any blood tests, scans or measurements, not even the 12-week scan. I would have liked to have had checks, but I couldn't afford an independent midwife, so I trusted my instincts.

I have always preferred to find my own path in life, and felt comfortable doing this. My family hated it – they wanted the reassurance of the professionals – but as far as I was concerned, I had produced one healthy baby, so I would produce another. My body didn't need help.

Thinking back, there were tiny clues that suggested this was a multiple pregnancy, but I dismissed them. When I was seven months pregnant, a friend said she could feel a head in one position but I thought I could feel it in another. I discounted twins, though, because we didn't have any in our family.

Then there was the party in my belly that started whenever music was played. The tangle of limbs would kick in all directions, but I put it down to my baby being vigorously healthy.

I went into labour six weeks early – which is common with twins – and as I laboured in my flat, I realised it wasn't progressing like the birth of my son. His had been four hours of alternating agony and ecstasy, whereas this was just grinding pain that dragged on for the whole day.

I had taught myself how to do an internal examination, so I could feel I was fully dilated. I had laboured for 10 hours, but now, instead of a head, I felt something bony. It didn't feel right at all. I knew I shouldn't push, and I went into hospital later that evening.

An ambulance took me to the delivery room, where a doctor examined me. He decided it was a head after all, and I began to push. After a moment, a tiny bottom and then two legs unfurled themselves from my body. My baby was breech. But her head was refusing to come out. It seemed to be stuck, so I was put up in stirrups so the doctor could investigate. As he examined me, his eyebrows shot up. "It's twins!" he shouted.

The reason my baby's head was wedged was that it was being blocked by her sister. It was an incredible way to find out I was having twins – when both their lives were in danger. I couldn't digest this information properly, though, because the doctor was busy pushing the second baby back up. Once he'd done this, he could deliver the first baby's head with forceps, and her sister tumbled out behind her seconds later.

Both babies were very little – just three pounds each – and their lungs weren't fully developed. I got only a glimpse of them before they were dashed off to special care. Suddenly alone, I struggled to take it all in. I had identical twin girls. The trauma and stress instantly felt irrelevant. To have two babies with one pregnancy was a miracle – double the luck. Even as they were whisked away from me, I felt nothing but elation.

My girls, Sapphire and Blue, were in hospital for six weeks; we were allowed to take them home when they reached full term. I feel a pang of guilt when I think that my refusal of medical intervention deprived them of steroids in the womb. These are used to develop lungs if a birth is likely to be premature. But this is tempered by the fact that my pregnancy was calm because I wasn't constantly monitored and filled with anxieties. I am, however, relieved and grateful that they were born in hospital, because it saved their lives.

After we took them home, I grappled with the demands of two newborns. In the early months I gave up hope of ever having a spare moment, but as they grew the advantages of having twins revealed themselves – how lovely it is to have a constant playmate.

My two girls are eight now and have blossomed into wonderful people with very different personalities. In hindsight, I am glad I didn't know I was having twins. If it happened again, I still wouldn't find out – why would I want to miss out on the best surprise of my life?

• As told to Emily Cunningham

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