A woman with two wombs who is believed to be the first in the world with the rare condition to give birth to triplets took them home yesterday.

Hannah Kersey, 23, was unaware that she had uterus didelphys until her first child Marley was born 22 months ago. But the biggest shock came when she went for a scan 12 weeks into her second pregnancy and was told that she was carrying a set of twins in one womb and a baby in the other.

Although there have been more than 70 recorded instances of women with the condition getting pregnant in both wombs simultaneously, doctors have been unable to find a previous case of triplets.

Ruby, Tilly and Gracie were born in September. They were delivered by Simon Grant, a consultant in obstetrics and foetal medicine at Southmead Hospital, Bristol, and kept in hospital for three months because they were underweight. Dr Grant said: “We haven’t been able to find a case where there has been twins and a single. There are very few world firsts nowadays, but this may certainly be one.”

The girls were conceived from two eggs produced during ovulation, one in each womb. One egg split, producing the identical twins Ruby and Tilly, while Gracie developed independently.

When they were delivered by Caesarean section seven weeks prematurely, Ruby and Tilly weighed 2lb 6oz and 2lb and Gracie weighed 2lb 13oz. The total weight of all three baby girls was only slightly heavier than the average weight of one.

Uterus didelphys is believed to affect about 1 in 1,000 women in Britain, although one is often significantly larger than the other, making a double pregnancy unlikely.

It can also run in families. Ms Kersey’s mother, Nicola, 41, and sister, Rebecca, 17, both have two wombs. The wombs are usually no more than half the normal size, which makes it difficult for the pregnancy to run to full term.

Ms Kersey and her partner, Mick Faulkner, 23, from Northam, Devon, were faced with an agonising decision when they were told that she was pregnant with triplets.

She said: “We were given three options and had to make our choice quite quickly. The first was to terminate all three babies, the second was to terminate the twins and carry on with one foetus, and the third was to keep all three children and pray they would make it through.

“I immediately knew that I could not put an end to the life of any of my unborn children, so we elected to carry all three.

“It feels like a miracle to have all made it and be doing so well.”