Twin anemia polycythemia sequence (TAPS) is a chronic form of unbalanced feto-fetal transfusion through minuscule placental anastomoses in monochorionic twin pregnancies, leading to anemia in the... Show moreTwin anemia polycythemia sequence (TAPS) is a chronic form of unbalanced feto-fetal transfusion through minuscule placental anastomoses in monochorionic twin pregnancies, leading to anemia in the donor twin and polycythemia in the recipient twin. TAPS can occur spontaneously in up to 5% of monochorionic twins or can arise in 2%-16% of cases after incomplete laser surgery for twin-twin transfusion syndrome. TAPS can develop across the entire second and third trimester. Antenatal diagnosis for TAPS is reached via Doppler measurement of the fetal middle cerebral artery peak systolic velocity, showing an increased velocity in the donor, combined with a decreased velocity in the recipient. Treatment options for TAPS include expectant management, preterm delivery, intrauterine blood transfusion with or without a partial exchange transfusion, fetoscopic laser surgery and selective feticide. The best treatment option is unclear and is currently being investigated in an international multicenter randomized trial (the TAPS trial). Spontaneous fetal demise occurs in 5%-11% of TAPS twins, more often in donors (8%-18%) than in recipients (2%-5%). Severe long-term neurodevelopmental impairment is seen in 9% of TAPS twins, with donors having an increased risk for cognitive impairment and hearing problems (15%). Show less
This thesis deals with various aspects of twin anemia polycythemia sequence (TAPS). TAPS is a condition that can develop due to unbalanced feto-fetal blood transfusion through minuscule vascular... Show moreThis thesis deals with various aspects of twin anemia polycythemia sequence (TAPS). TAPS is a condition that can develop due to unbalanced feto-fetal blood transfusion through minuscule vascular placental anastomoses in monochorionic twin pregnancies, causing the donor twin to become anemic and the recipient twin to become polycythemic. In this thesis we show that a difference in middle cerebral artery peak systolic velocity (MCA-PSV) > 0.5 Multiples of the Median (MoM) has a high diagnostic accuracy for the the antenatal diagnosis of TAPS. For postnatal diagnosis of the condition, inspection of the color of the maternal side of the placenta can be of great value. Furthermore, we present the results of a large international registry, and report on outcomes after different treatment options for TAPS. As the best treatment for TAPS is unclear, we propose the protocol of The TAPS Trial (a multicenter open-label international RCT) to investigate the potential beneficial effect of fetoscopic laser surgery for the outcome in TAPS twins . In the last chapters of this thesis we discuss short- and long-term outcome and show that TAPS donors show significantly higher rates of perinatal mortality and long-term neurodevelopmental impairment than their recipient co-twins. Show less
