Twin Anemia Polycythemia Sequence (TAPS)

Causes of TAPS

TAPS occurs spontaneously in approximately 6% of monochorionic twins and, when spontaneous, is most often diagnosed after 26 weeks’ gestation. It is also seen to occur in a small number of cases after fetoscopic laser surgery for TTTS.

Diagnosis of TAPS

Prenatally, the hemoglobin levels can be estimated from measuring blood flow through the fetal brain with middle cerebral artery Doppler ultrasounds. The blood flow in the brain of one fetus will be elevated, suggesting anemia, and the other fetus will have low blood flow velocities, suggesting a high hemoglobin. At birth, pregnancies complicated with TAPS will have a significant difference in hemoglobin levels between the two fetuses.

Treatment of TAPS

Currently, the best treatment for TAPS has not been established and options may be guided by gestational age. Potential treatment options may include a blood transfusion to the anemic fetus or fetoscopic laser ablation for spontaneous TAPS depending on gestational age. If the gestational age is advanced, the best treatment may be delivery.

Why choose Michigan Medicine?

The Michigan Medicine Fetal Diagnosis and Treatment Center has extensive experience caring for all types of multiple gestations. Our maternal fetal medicine physicians provide the highest level of prenatal assessment and delivery planning and our neonatology physicians provide neonatal intensive care for those pregnancies that do require preterm delivery.

Make an appointment

To make an appointment, please call 734-763-6295.