Body Talk: Two little miracles; Twins Ella and Lilly Denham are lucky to be alive after doctors failed to notice that they were slowly strangling each other in their mother's womb.

Byline: JANE PURCELL

WHEN Karen Denham gazes at her beautiful twin daughters sleeping contentedly in their cots, she feels much more than maternal pride - she also experiences an overwhelming sense of relief that they are alive.

While still in their mother's womb, Ella and Lilly were slowly strangling each other to death - and it's nothing short of a miracle that they survived.

Moments after the girls were born it was discovered that their umbilical cords were completely knotted and fused together and had risked fatally cutting off their oxygen supply.

The condition, known as cord entanglement, is so rare that even experienced doctors can fail to notice it. Around 30 per cent of twins who develop it will die in the womb.

Indeed, doctors had failed to detect Ella and Lilly's horrendously knotted cords despite Karen undergoing a scan every two weeks during the last three months of her pregnancy.

"We were told that Ella and Lilly were two very lucky little girls to have survived," says Karen.

"They are happy and healthy now, but there's never a day goes by without me looking at them and thinking how close I came to losing them both.

"It's scary to think that I could have lost them at such a late stage after I'd been carrying them inside me for so long."

The twins' knotted and fused umbilical cords were such an unusual sight that staff on the maternity ward came rushing over to look at them after the girls had been delivered. "A midwife who was not far off retirement was stunned and said she had never seen anything like it in her entire career," says Karen, 31, a graphic designer from Newbury, Berkshire.

"And the doctor who delivered them said: "Now that's what you call a proper knot'."

Karen and husband Rob, 35, a car body shop manager, were told they were expecting twins during their 12-week scan at their local hospital.

But their elation quickly turned to concern when routine tests showed there was no membrane separating the babies, which meant they shared both a sac and a placenta in what is known as a monoamniotic pregnancy.

It is extremely rare, very high risk and seen in only one per cent of all twins. Karen was told she would need very careful monitoring because of the complications and a Caesarian section was recommended.

While the biggest threat to monoamniotic babies is cord entanglement, they are also at risk from twin to twin transfusion syndrome (TTTS), another rare and often fatal complication which affects 10 to 15 per cent of identical twins sharing a placenta.

"We were excited and anxious at the same time," says Karen. "We didn't tell our families about all the risks because we didn't want to worry them.

"And although doctors mentioned the possible complications, it was only after the girls were born that we discovered how incredibly risky my pregnancy had been."

Karen was scanned monthly to begin with and then fortnightly when she reached the last trimester of the pregnancy. "Every time we went for a scan we would just hope and pray that the babies would be all right," she says.

Despite the worries, no sign of anything untoward was detected and the Caesarian was booked.

However, nature took its own course 10 days early when Karen's waters broke at 35 weeks. She was taken into hospital where the twins' heartbeats were closely monitored. Karen was also given antibiotics to prevent the babies contracting any infections.

Incredibly, a consultant then told Karen that she could give birth naturally, despite the fact that monoamniotic twins are nearly always delivered by Caesarian because of the danger of further cord entanglement.

After a 26-hour labour, Ella and Lilly arrived - one day before Rob and Karen's 10th wedding anniversary. Ella was born first, weighing 4lbs 6oz and Lilly arrived four minutes later weighing 4lbs 14oz. It was only after the girls had been delivered that their knotted and fused umbilical cords were discovered.

"The doctor who delivered them said: 'This is why multiple pregnancies should be delivered by Caesarian'," says Karen.

"We know now that I should never have been allowed to give birth naturally because it put the girls at even more risk. But we saw so many different consultants and they all said different things."

After Ella and Lilly were delivered, staff wheeled the placenta and cords into the recovery room on a trolley for Karen to look at.

Because they were so unusual, the cords were then photographed by the hospital for its research laboratory before being taken away to be analysed.

"It was such a big shock to be told that Ellie and Lilly came so close to dying because their cords were so twisted. The whole idea of scanning me every two weeks was to make sure nothing like this happened.

"The hospital should have picked up on it, but we don't feel angry. We're just so relieved that the girls are OK.

"Nobody can say when the cords fused together, but it looked like quite an old knot so we think they might have started getting tangled quite early on.

"Ella was a little wriggler and I could feel her tossing and turning around inside me so she must have been getting them both tangled up."

The premature girls had to be taken to the Special Baby Care Unit after their birth because they were unable to regulate their own body temperatures, their blood sugar levels were low, they had to learn to feed properly and Ella was slightly jaundiced.

After three weeks in hospital the twins were able to come home and now, almost a year on, they are thriving.

"They have an amazing bond," says Karen. "If you take one out of the room the other one will cry and they both have to go to bed together, otherwise there are tears.

"Every mother thinks her babies are extra-special, but I know that mine really are my two little miracles. It could have been a very different story.

"I must be the luckiest mother in the world."

What happened during Karen's pregnancy?

Monoamniotic pregnancy is an extremely rare and highly dangerous condition, often ending in the death of both babies in the womb.

Because the babies share the same amniotic sac and placenta, the biggest risk is from umbilical cord entanglement.

Only one in 10,000 twin pregnancies are monoamniotic. The condition causes an interruption in the blood flow to one or both babies where they may not receive enough nutrients or oxygen.

Why is it so risky?

Professor Nick Fisk of Queen Charlotte's Hospital, London, is an expert in multiple births and says: "Monoamniotic twins swim all over the uterus and drag their cords with them so that they become completely intertwined.

"Almost all will have tangled cords to some degree and we think this occurs very early in pregnancy. But in 30 per cent of cases the cord is pulled too tight and without specialist treatment the babies will die.

"This is such a rare condition that many smaller hospitals don't even recognise it and cord entanglement may not always be seen on less sophisticated scanners."

What are the treatments?

The majority of fatal cord accidents are gradual, so intensive monitoring and testing of the babies is essential to watch for signs of compression.

One option is treatment with a drug called Sulindac, which reduces the movement of the babies

Monoamniotic twins are normally delivered early, at 32 weeks, because the cord risks outweigh the prematurity risks. Commenting on Karen's case, Fisk says: "This lady should have been given a Caesarian to prevent the cords getting further twisted during labour.

"The cords normally get twisted to some extent in a monoamniotic pregnancy but for them to be fused together is incredibly rare."

Twin truths

Non-identical twins come from two eggs fertilised by two different sperm. But a third of all twin pregnancies are identical and result from a single egg being fertilised by a single sperm and then dividing into two identical embryos.

If division takes place in the first three days following fertilisation, the twins will have their own placenta and membranes and will look the same on a scan as non-identical twins.

However, when division takes place at any time after the third day, the twins share a placenta. Here's what else happens, depending on when the twins divide...

Monochorionic

When division occurs between the fourth and ninth day, both babies share a single placenta and an outer membrane.

Monoamniotic

If the embryos divide after the ninth day, the twins will be in a single sac.

Conjoined 

Division after the 12th day following conception results in conjoined (Siamese) twins which are extremely rare.

Twin-to-Twin Transfusion Syndrome

TTTS is a rare complication affecting identical twins who share a placenta. Just 1,000 cases occur every year in the UK, of which 80 per cent die undiagnosed. Even when treated, 35 per cent of cases will still end in death. With TTTS, the babies themselves are healthy - the abnormalities are in the placenta.

Twins sharing a placenta also share a blood supply which leads to a risk that one twin will receive too much blood and become overloaded with fluid, putting a strain on its heart. As a result, the other twin will get too little blood and may not grow.

CAPTION(S):

SURVIVORS: Ella and Lilly were kept in hospital for three weeks; NORMAL: Most twins develop in their own; separate sacs, so; there's no risk of their cords getting tangled; RISKY: Sharing one sac, Lilly and Ella's cords twisted together, threatening to cut off their blood and oxygen supply