In a groundbreaking move, UK researchers have made significant strides towards a non-invasive solution for twin-to-twin transfusion syndrome (TTTS), a life-threatening condition affecting identical twin pregnancies. This world-first study, led by Imperial College London and funded by the Medical Research Council (MRC), has shown promising initial results that high-intensity focused ultrasound (HIFU) could offer a safer alternative to existing treatments.
TTTS occurs in around 10-15% of identical twin pregnancies, where babies share a placenta. This affects an estimated 300-400 pregnancies annually across the UK. The condition arises from an imbalance in blood flow between the twins, with one receiving too much and the other too little. If left untreated, TTTS can cause organ failure in both babies, and in severe cases, result in the death of one or both.
Currently, the primary treatment for TTTS involves a procedure where a small telescope-like device is inserted into the womb to block blood flow with a laser. While often successful, this method carries risks, including damaging the amniotic sac and potentially causing miscarriage due to an incision in the mother's abdomen.
The feasibility study, published in the American Journal of Obstetrics and Gynaecology, used ultrasound-guided HIFU between 12 and 17 weeks of pregnancy. This technique uses Doppler ultrasound to identify tiny connecting blood vessels in the placenta. A device outside the body then generates high-energy sound waves to heat and block blood flow through these vessels, aiming to rebalance circulation between the twins.
The study involved 10 women from the UK and Europe and found that the procedure successfully blocked blood flow in 90% of targeted placental vessels. Dr Adam Babbs, Associate Director of Translational Research at UKRI MRC, highlighted the significance, stating that this 'proof of concept' offers a non-invasive method for earlier intervention, potentially improving outcomes for affected babies.
Professor Christoph Lees described the research as 'very promising', confirming safe use in TTTS for the first time. He expressed hope for further trials involving 50-100 women to determine its effectiveness and establish if it could be a less risky option for families.
While these early results are encouraging, researchers stress that the study has not definitively proven clinical effectiveness or improvement in survival rates. Larger trials are necessary to fully assess efficacy and safety before this innovative approach can become a standard treatment option for TTTS.