Identical twins with twin-to-twin transfusion syndrome (TTTS) that had intrauterine laser ablation surgery have been safely delivered at St George’s.

Olivia and Charlotte were born on 18 February 2019 after being diagnosed with TTTS at sixteen weeks gestation. The condition was discovered when mum, Alexandra, 38, had a scan showing an uneven volume of amniotic fluid surrounding both babies.

TTTS affects around 10-15% of identical twins and occurs when there is an uneven flow of blood in the vessels connecting the twins. This means that one twin doesn’t receive enough blood and nutrients to grow and becomes anaemic, and the other twin gets too much blood, which causes heart and circulation problems.

Alexandra was referred to Professor Basky Thilaganathan and Professor Asma Khalil, specialists in multiple pregnancies at St George’s, who advised she undergo emergency laser ablation surgery.

Alexandra said: “My husband and I met with Professor Thilaganathan and were instantly put at ease by his wonderful compassionate and respectful manner. While scanning me, he explained the things we were concerned about, such as the babies’ bladders and amniotic fluid, and also the things that delighted us; the tiny toes and cute noses of our daughters that we were so desperate to protect.

“He confirmed it was the start of TTTS and explained exactly what this meant in all the detail that I felt I needed and at no time did I feel rushed or silly – he took the time to answer all of our questions. He told us he could do the surgery in a few days, if we needed to sort things out at home or with work, or he could do it the next day.”

Alexandra’s surgery took place the following morning. During the procedure, a small instrument (fetoscope) is inserted through an incision in the mother’s abdominal wall and uterus. A laser fibre is then inserted into the fetoscope to seal off blood vessels in the shared placenta, so that both babies receive a more equal supply of blood.

After the laser surgery, excess amniotic fluid is also removed. If left untreated, there was a 90% chance that both twins wouldn’t survive. There are approximately 400 cases of twin-to-twin transfusion syndrome across the UK each year and 60 of these are referred to St George’s.

Five hours after surgery, Alexandra had a scan revealing the procedure had been a success. She said: “I held my breath while Professor Thilaganathan scanned me, but he very quickly said ‘There you go, there are your two girls’ heartbeats and they look good’. I burst into tears of relief!”

She added: “My incision was just a tiny little cut, not much bigger than a paper cut, which amazed me thinking what had been done to me to save my babies.”

Within a few weeks, the weight discrepancy between the twins went from 36% to less than 20%.

Alexandra continued visiting St George’s for regular scans, which showed the twins growing and developing healthily. Due to the nature of the procedure and it being a multiple pregnancy, she was advised that there was a high probability of having a preterm labour.

At 32 weeks gestation, Olivia was born weighing 3.5lbs, followed a few minutes later by her twin sister, Charlotte, weighing 4.4lbs.

Professor Basky Thilaganathan, Director of St George’s Fetal Medicine Unit said: “This is a fantastic outcome, made even more exciting by the fact we’ve recently been recognised as one of only four fetal surgery centres in the country, leading to a major NHS funding award to support us going forward. This is thanks to new fetal surgery equipment, funded by St George’s Hospital Charity, which means we’re able to carry out more live-saving procedures for twins like Olivia and Charlotte.”

The twins, now seven months old, are both happy and healthy. Alexandra, who lives in Morden with her husband Nicholas and their three other children said: “I am so grateful to Professor Thilaganathan, Professor Khalil and the team at St George’s. The care and immediate attention I received was fantastic. The whole time I felt ‘in the loop’ and that I was being well looked after.”

Professor Asma Khalil, Consultant in Obstetrics and Fetal Medicine, who supported Alexandra throughout her treatment, said: “It was understandably a very difficult time for Alexandra and her husband. We supported them from diagnosis and through treatment, ensuring they felt comfortable and confident with the process. By making an early diagnosis and offering prompt treatment we’ve been able to ensure the safe delivery of two healthy baby girls – it’s fantastic!”

Notes to editors

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