Pioneering treatment saves identical twins from rare pregnancy condition

New Delhi, India Jul 10, 2026 ALN: A pioneering procedure using high-powered sound waves has the potential to treat identical twins affected by a serious but rare condition during early pregnancy, a study has found.

Blood flow between babies with twin-to-twin transfusion syndrome (TTTS) is uneven, leaving one baby dangerously small and the other too large, putting their survival at risk. This condition arises when identical twins share a placenta, a situation that occurs in approximately 10-15% of identical twin pregnancies. In the UK, this translates to about 300-400 pregnancies each year. The imbalanced blood flow can lead to severe complications, including the risk of heart failure for the larger twin, known as the recipient, and inadequate growth and development for the smaller twin, known as the donor.

Brioney Garrett's identical girls' lives were in danger during her pregnancy before doctors at a London hospital used the treatment to seal blood vessels causing the problem, without needing an operation. The innovative approach allowed for a non-invasive intervention, which is a significant advancement over traditional methods that typically involve inserting a needle into the womb to either drain excess fluid or seal blood vessels using a laser. These traditional methods can be invasive and carry risks for both the mother and the babies.

Following the world-first treatment, Nancy and Margo were born healthy and, now aged four, will soon start school. Their successful outcome highlights the potential of this new treatment method to improve the chances of survival for twins affected by TTTS.

Half of the 10 women who took part in the trial required further treatment, and 12 of 20 twin babies survived following the procedure, as reported in the American Journal of Obstetrics & Gynecology. The results of the study are promising, but researchers emphasize the need for larger-scale studies to validate the effectiveness of this treatment before it can be widely offered to expectant mothers facing similar challenges.

The researchers, from Queen Charlotte's and Chelsea Hospital, said it was "extremely exciting" to have a non-invasive method to treat the condition, without the need to put a needle or telescope into the mother's tummy. This development represents a significant shift in how TTTS might be managed in the future, as it reduces the risks associated with invasive procedures.

Brioney expressed her gratitude for the innovative treatment, stating that her daughters were "my miracle twins." She reflected on the precarious situation they faced and how she remains grateful for their health. "We were in a very dire situation and I don't forget that," she said. "It stays with me always how things could have been. Every day I still count my blessings." Her story underscores the emotional toll that TTTS can have on families and the importance of effective treatment options.

TTTS occurs due to an imbalance in the placental blood supply, leading to a build-up of excess fluid around the larger recipient baby and a dangerous lack of fluid around the smaller donor baby. This imbalance can cause serious complications for both twins, including neurological damage, growth issues, and even death. The condition can progress rapidly, making early detection and intervention critical.

Block blood flow

For Brioney, the procedure was more straightforward and took about 20 minutes. She lay flat as a specially-designed machine fired high-powered ultrasound waves at tiny blood vessels in her placenta. "It was very quick and pretty painless," she said. This non-invasive technique uses focused ultrasound energy to precisely target and seal the problematic blood vessels, effectively rebalancing the blood flow between the twins.

Brioney and the other pregnant women, who were from the UK and across Europe, took part in the study after scans detected the condition during early pregnancy. The ability to intervene early is crucial, as TTTS can lead to dire consequences if not addressed promptly. The study's design emphasizes the importance of early detection through routine ultrasound screenings, which are standard in prenatal care.

Prof Christoph Lees, head of fetal medicine at Imperial College Healthcare NHS Trust and professor of obstetrics at Imperial College London, said the research was "very promising." He noted that if this method could be validated in larger studies, it could provide hope to many women who might otherwise face invasive treatments with associated risks. The implications of this research extend beyond individual cases, potentially reshaping the standard of care for high-risk twin pregnancies.

Ultrasound is regularly used in medical scans to produce images of the body, and is known to be very safe - but this type of ultrasound is completely different and much more focused. The heat created by its beams can seal blood vessels just 2mm in diameter, about 5-6cm below the skin. This precision is vital for ensuring that only the targeted vessels are affected, minimizing the risk of damage to surrounding tissues.

The procedure blocked blood flow in 90% of the blood vessels treated as part of the study, and there were no unwanted side-effects reported. This high success rate is encouraging and suggests that the technique could become a viable option for treating TTTS in the future.

The charity Twins Trust, which supported the study, said the new approach could make a real difference. "Any procedure that is non-invasive and can potentially identify TTTS earlier and improve outcomes for our families with this life-threatening condition could be a turning point," said Helen Peck, head of healthcare engagement and research. The advocacy of organizations like Twins Trust highlights the importance of ongoing research and innovation in maternal-fetal medicine.

Weeks after Brioney's scan, it was clear the procedure had worked - the blood flow to the babies had been rebalanced, although there were other issues during the course of her pregnancy. Scans showed Margo, who did not have enough fluid around her, "was in a much better position," Brioney said, and "the strain on Nancy's heart had eased." This positive outcome reinforces the potential of the new treatment to alter the course of pregnancies complicated by TTTS.

The twins were born at nearly 34 weeks - Nancy weighing 3lbs 7 and Margo 3lbs 3 ounces. Both girls were healthy, and Brioney noted that Margo wasn't as small as they had initially feared. The successful birth of Nancy and Margo serves as a testament to the effectiveness of the new treatment and the resilience of families facing such challenging circumstances.

In September, they start primary school. "They're funny, smart, energetic little girls that just fit right in with their age group," Brioney said. Their story is not only one of survival but also of hope and the potential for advancements in medical technology to change lives. As research continues and more studies are conducted, the hope is that more families will benefit from non-invasive treatments for conditions like TTTS, leading to healthier outcomes for both mothers and their babies.