What is Twin to Twin Transfusion Syndrome?
Twin to Twin Transfusion Syndrome (TTTS) is a serious prenatal condition that affects identical twins or higher-order multiples who share a
monochorionic placenta. This syndrome occurs when the blood flow between the twins becomes unbalanced, leading to one twin (the donor) giving blood to the other twin (the recipient).
What Causes TTTS?
TTTS is caused by abnormal blood vessel connections in the
shared placenta of monochorionic twins. These vessel connections allow blood to flow unevenly between the twins. The donor twin can suffer from decreased blood volume and poor growth, while the recipient twin may experience overcirculation, leading to heart failure.
Discrepancies in amniotic fluid levels: The donor twin may have low fluid (
oligohydramnios), and the recipient twin may have too much fluid (
polyhydramnios).
Size differences: The donor twin may be smaller and show signs of
intrauterine growth restriction (IUGR).
Cardiac issues: The recipient twin may develop heart problems due to the extra blood volume.
How is TTTS Diagnosed?
TTTS is usually diagnosed through routine prenatal ultrasounds. Detailed Doppler studies can further assess the severity of the condition. The
Quintero staging system is often used to classify the severity of TTTS from Stage I to Stage V based on ultrasound findings and the health of the twins.
Amnioreduction: This procedure involves removing excess amniotic fluid from the recipient twin's sac to balance fluid levels.
Laser therapy: Selective fetoscopic laser photocoagulation (SFLP) can seal off the abnormal blood vessel connections in the placenta.
Medications: Certain medications may help manage symptoms or complications associated with TTTS.
Early delivery: In some cases, delivering the babies early may be the best option if the condition is too severe to manage in utero.
Preterm birth
Neurological complications
Heart problems in the recipient twin
Possible stillbirth for one or both twins
Early and effective treatment can help mitigate some of these risks, but close monitoring is essential.
What is the Prognosis?
The prognosis for twins with TTTS varies based on the severity of the condition and the effectiveness of the treatment. With advancements in medical technology, the survival rates and long-term outcomes have improved, especially with timely intervention. However, ongoing medical care and follow-up are often necessary to manage any long-term complications.
Conclusion
Twin to Twin Transfusion Syndrome is a complex and serious condition that requires specialized care and monitoring. Early diagnosis and intervention are crucial in improving outcomes for affected twins. Pregnant women with monochorionic twins should undergo regular ultrasounds to detect any signs of TTTS early on.
