Objectives: We report an atypical case of twin-twin transfusion syndrome (TTTS) in monochorionic-diamniotic twins with arterio-arterial anastomoses in which the former donor became the recipient during pregnancy.
Methods: Serial sonographic monitoring was performed.
Results: There was a phenotype reversal in TTTS concerning growth and amniotic fluid ending at 27 weeks, with the dominance of the former smaller donor. Doppler sonography changed from absent enddiastolic flow of the donor to normal values in both twins. The new recipient showed transient ascites, the now smaller actual donor (former recipient) developed progressive cardiomegaly, hypertrophy of the myocardium and mitral and tricuspid insufficiency at 29 weeks. Doppler sonography in the new donor deteriorated to highly pathologic flow in the venous system, leading to cesarean section. The donor fetus died 12 h after delivery because of myocardial decompensation. The recipient did very well and was discharged 8 weeks later from the neonatology unit.
Conclusion: This atypical course shows the importance of serial sonographic monitoring in pregnancies with TTTS.
Copyright (c) 2004 John Wiley & Sons, Ltd.