When doctors discovered Danielle Young was pregnant they were amazed. She had been diagnosed with having two wombs - a rare condition that makes it difficult to carry a baby to full term.
Furthermore one fallopian tube was completely blocked which means only one of her two wombs was supposedly functioning properly.
So they were even more amazed when they made a second startling discovery - that she was pregnant with twins - one in EACH womb - in staggering odds of FIVE MILLION to one. In fact, research shows there are fewer than a hundred women worldwide who have ever fallen pregnant with two babies in two separate wombs.
Both twins were born safely thankfully, after medical experts had warned Danielle that she could lose both babies.
Professor of Obstetrics Andrew Shennan, from Kings College Hospital in London said: "An obstetrician will see a case like this once in a lifetime.
"The egg must have come down the fallopian tube that doctors thought was previously blocked. It is extremely unusual."
Danielle, 29, a full-time mum, had defied medical odds already to give birth to her daughter Paige, now five.
She had been diagnosed with a bicornuate uterus at the age of 18. The condition meant her womb was completely split in two and the two halves were sealed off from each other, making two separate wombs.
She also has a double cervix and a double vagina. But one fallopian tube was completely blocked, which meant that it would only be possible for her to fall pregnant in one womb.
But having two smaller wombs, also meant that it would be difficult for her to carry a baby to full term.
Danielle, who lives with her husband Richard, 39, a plumber, in Bridgwater, Somerset, says:
I knew that because of my condition it would be unlikely that I would ever be a mum. It was devastating because I loved children, but I had to accept that it wasn't going to happen.
The couple went to see a fertility consultant to ask about the possibility of having IVF treatment to help them conceive.
Because of the left womb being blocked, she was put on the waiting list for IVF treatment. But doctors warned her that even if she fell pregnant it would be unlikely that her remaining womb would be big enough to carry a baby to full term.
"I wanted to give it every possible chance and there was no way I was giving up that tiny bit of hope. So we went on the waiting list for treatment," explains Danielle.
But several days later, before any treatment could start, Danielle started to feel ill. Her husband persuaded her to do a pregnancy test and they discovered that she had fallen pregnant naturally:
We were both shocked. After everything the doctors had said, I was actually pregnant. I was given regular scans and the doctors said they couldn't promise that I would be able to carry the baby, but she hung on.
Paige was born in February 2007 at St Michaels Hospital in Bristol, and just five months later Mrs Young started feeling unwell once more.
Tests showed she was pregnant again - and this time it was a double shock. She was pregnant in both wombs!
"It was unbelievable to even find out that I was pregnant again. It was such a shock. When I went for the scan the sonographer ran the scanner over my stomach and we could see the heartbeat," says Danielle.
"Then she looked at the screen with a puzzled expression, moved the scanner slightly, and there was another heartbeat in the other womb. I was pregnant with twins.
"No-one could explain how I'd fallen pregnant in that womb as the tube on that side was completely blocked. It just seemed like a miracle. They could see that there were two babies in my two wombs and they were both alive. But they couldn't understand how the other baby had managed to get in there.
The doctors were baffled. They couldn't even guarantee that they had been conceived at the same time - I may have fallen pregnant twice, two weeks apart.
The doctors warned her that it was unlikely that both babies would survive to full term, especially the twin who was in the smaller left womb.
Danielle was scanned every week at St Michael's Hospital in Bristol, until she reached six months, when she went into premature labour in December 2007.
Doctors tried to halt her labour, but hours later the twins were delivered by emergency caesarean, Joshua weighing a tiny 2Ib, 6oz, and Leah weighing a smaller 2Ib, 2oz.
"I was wheeled down to see them and they were so tiny lying there in their incubators," says Danielle.
Doctors were at first worried that Leah had suffered brain damage, but tests later showed she was fine:
They really astounded doctors with their progress. Leah was such a fighter. Even though she was the smaller of the two she was the first to feed and she was able to breathe on her own before Joshua.
The twins have recently celebrated their fourth birthday and they are now the correct height and weight for their age.
"When they are older I will tell all three of my children how they were born against all the odds. People think they are triplets because they are so close in age," says Danielle.
"When I look at them I know that miracles certainly do happen."
Words: Lucy Laing at Worldwide Features
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