What is Twin to Twin Transfusion Syndrome (TTTS)?
Twin to Twin Transfusion Syndrome (TTTS) is a complication that can occur in pregnancies where identical twins share a single placenta (monochorionic twins). In TTTS, the blood flow between the twins becomes unbalanced due to abnormal blood vessel connections in the shared placenta. This can lead to one twin (the donor) transferring more blood to the other twin (the recipient), causing significant health risks for both.
How Common is TTTS?
TTTS affects about 10-15% of monochorionic twin pregnancies. This condition does not occur in all identical twin pregnancies but is a significant concern in those that share a placenta.
Discrepancy in amniotic fluid levels between the twins (polyhydramnios in the recipient twin and oligohydramnios in the donor twin).
Size differences between the twins.
Visible differences in the bladder size of the twins.
Differences in the growth rates of the twins.
What are the Risks Associated with TTTS?
TTTS poses serious risks to both twins. The
donor twin may suffer from anemia, growth restriction, and insufficient amniotic fluid, while the
recipient twin may develop heart failure, excessive amniotic fluid, and other complications. Both twins are at risk of preterm birth, which can lead to further complications.
How is TTTS Diagnosed?
Diagnosis is typically made through detailed ultrasound examinations, which can reveal the characteristic signs of TTTS. Doppler ultrasound may also be used to assess the blood flow patterns between the twins.
Amnioreduction: This procedure involves the removal of excess amniotic fluid from the sac of the recipient twin to balance fluid levels.
Laser Therapy: This treatment, known as fetoscopic laser photocoagulation, involves using a laser to seal off the abnormal blood vessel connections in the placenta.
Selective Reduction: In severe cases, selectively reducing the number of fetuses may be considered to improve the survival chances of the remaining twin.
Amniotic Septostomy: This procedure creates a hole in the membrane separating the twins to allow fluid to balance between the sacs.
What is the Prognosis for TTTS?
The prognosis for TTTS varies widely based on the stage at which it is diagnosed and the effectiveness of the treatment. Early detection and timely intervention can significantly improve outcomes. However, TTTS remains a high-risk condition, and ongoing monitoring throughout the pregnancy is crucial.
What are the Long-term Outcomes?
The long-term outcomes for twins affected by TTTS depend on several factors, including the severity of the condition and the success of the treatment. Some twins may experience long-term developmental and neurological issues, while others may have no lasting effects.
Neonatal care and follow-up are essential to monitor for any potential complications.
How Can TTTS be Prevented?
Currently, there is no known way to prevent TTTS. However, early and regular prenatal care with specialized monitoring for monochorionic twin pregnancies can help detect and manage the condition promptly.
Conclusion
Twin to Twin Transfusion Syndrome is a serious condition that requires careful monitoring and intervention. Advances in prenatal care and treatment options have improved the outcomes for many affected pregnancies, but the condition still poses significant risks. Expectant mothers with monochorionic twins should work closely with their healthcare providers to ensure the best possible care for their twins.
