Twin to Twin Transfusion services offered in Chicago, IL
Some pregnancies require more advanced care, including those shaped by a condition called twin-to-twin transfusion. Treating this condition is one of many services available from Dr. Suwan Mehra, MD, who serves Chicago, Illinois and the Tri-state area. Contact Dr. Mehra’s office if you’d like more information about this condition and the treatment options available.
Twin-to-Twin Transfusion Syndrome (TTTS) is a serious condition that can occur in identical twins—or higher-order multiples—who share a single placenta, a situation known as a monochorionic pregnancy. While all identical twins share a placenta, only about 10 to 15 percent will develop TTTS. This condition does not affect fraternal twins, who each have their own placenta.
In a shared placenta, the babies are connected by small blood vessels. In most cases, blood flow between the twins is balanced, allowing both babies to grow and thrive. However, in TTTS, this balance is disrupted. One baby (the “donor” twin) transfers blood to the other (the “recipient” twin), creating a mismatch. As a result, the donor twin may become dehydrated and produce little or no urine, leading to a low amount of amniotic fluid. In contrast, the recipient twin can become overloaded with blood, producing too much urine and accumulating excessive amniotic fluid.
Without treatment, TTTS can pose serious health risks to both babies. The donor twin may experience slowed growth, while the recipient twin is at risk of heart complications due to the extra blood volume. Prompt diagnosis and intervention are essential, and advanced fetal therapies—including minimally invasive laser surgery—can significantly improve outcomes.
In some cases, a milder but related condition called Twin Anemia-Polycythemia Sequence (TAPS) may occur. This happens when only red blood cells—not fluid—are exchanged through tiny, narrow vessel connections in the placenta. Over time, one baby becomes anemic (with too few red blood cells), while the other develops polycythemia (an excess of red blood cells, causing the blood to become thick). Unlike classic TTTS, amniotic fluid levels in TAPS typically remain normal, making diagnosis more challenging and reliant on specialized Doppler ultrasound assessments.
The placenta is a remarkable organ that nourishes and supports babies throughout pregnancy, delivering oxygen and vital nutrients as they grow. In pregnancies where twins share a single placenta, they are also connected by shared blood vessels within that placenta. While the exact cause of Twin-to-Twin Transfusion Syndrome (TTTS) is not fully understood, we know that sometimes the normal pattern of blood flow between these shared vessels becomes unbalanced.
When this happens, one baby begins to receive more blood than the other. The baby receiving too little blood may become growth-restricted and develop low amniotic fluid, while the baby receiving too much is at risk of heart strain and excess fluid. This uneven circulation is what leads to TTTS. It’s not caused by anything a parent did or didn’t do, and it can develop without warning—making early diagnosis and expert monitoring critically important.
TTTS is diagnosed through ultrasound, which allows us to monitor the babies’ growth, amniotic fluid levels, and blood flow in real time. A key sign of TTTS is an imbalance in amniotic fluid—where one baby has too much fluid and the other has too little. In some cases, changes in blood flow patterns within the umbilical cords or fetal hearts may also be seen.
Pregnant individuals may also notice symptoms such as a sudden or rapid increase in abdominal size, which can signal excessive amniotic fluid around one baby.
Because TTTS can progress quickly, early and frequent monitoring is essential. For pregnancies where twins share a placenta (monochorionic), we recommend ultrasounds every two weeks starting at 16 weeks’ gestation. In the third trimester, the frequency of ultrasounds often increases to ensure that any changes are detected and addressed promptly.
With careful monitoring and timely diagnosis, families can feel empowered and supported in making the best decisions for their babies.
Early diagnosis and timely intervention are essential in managing Twin-to-Twin Transfusion Syndrome (TTTS). The best treatment approach depends on how far along the pregnancy is and the stage of TTTS at the time of diagnosis. Dr. Mehra and his team will guide you through all available options with compassion and clarity, helping you understand what’s best for your babies in your unique situation. Common treatment options include:
The long-term outlook for babies affected by Twin-to-Twin Transfusion Syndrome (TTTS) depends on how early the condition is diagnosed and treated, as well as how far along the pregnancy is at the time of delivery. Generally, the sooner treatment is provided—and the longer the babies remain safely in the womb—the better their chances for a healthy outcome.
Without treatment, advanced TTTS carries a high risk of complications, and survival rates are low. However, with timely intervention—particularly fetoscopic laser surgery—those outcomes improve significantly. In nearly 90% of treated pregnancies, at least one baby survives and thrives after birth. In high-volume fetal therapy centers across the country, both twins survive in approximately 70% of treated cases.
Every pregnancy is unique, and while these statistics provide important context, Dr. Mehra and his team focus on the individual needs of each family. We are here to guide you with clear information, honest expectations, and unwavering support—every step of the way.
Because Twin-to-Twin Transfusion Syndrome (TTTS) can affect multiple organ systems and development, long-term follow-up is often an important part of your babies’ care. Even after a successful treatment and delivery, continued monitoring helps ensure that any potential challenges are identified early and managed proactively.
Your babies will be supported by a dedicated team of specialists who understand the unique needs of children affected by TTTS. This care team typically includes a pediatrician who coordinates overall care, as well as pediatric cardiologists, developmental specialists, and other experts as needed. Together, they’ll work closely with your family to create a personalized follow-up plan tailored to your babies’ specific health and developmental needs.
Our goal is not only to treat TTTS before birth, but to support your family through every chapter that follows—with thoughtful, coordinated care and a long-term commitment to your children’s well-being.
