We present a particular case of TRAP (twin reversed arterial perfusion) syndrome, which has a very rarely association of the simultaneous existence of a rudimentary malformed heart and brain, and also other malformations like abdominal wall abnormality, absent bladder with present kidneys, and absence of the lungs, which appear only in a few cases on the receptor twin from this sequence, malformations incompatible with life. A Caucasian 26-year-old pregnant woman, at the first pregnancy, with a monochorionic-diamniotic pregnancy, 26 weeks of gestation was referred to our hospital, for polyhydramnios. The patient delivered a living female newborn, weighing 950 g, with an Apgar score of 2 at one minute - the donor fetus and a second female newborn with multiple malformations, no signs of life and who weighed 2300 g - the receptor fetus. The anatomopathological examination confirmed the TRAP sequence associated with severe facial dysmorphism, bilateral phocomelia and cardiac malformations (rudimentary hypoplastic, univentricular) and a vascular anastomosis between the two umbilical cords. Anemia and cardiac complications which can lead to cardiac failure, appear early during pregnancy and caused the death of the pumping twin. We emphasize that in our case of TRAP sequence, the ultrasound examination established the diagnosis of the syndrome with high accuracy. Therefore, we can conclude that the existence of a rudimentary heart and a vascular anastomosis between the two umbilical cords supports the apparition of TRAP sequence. The early diagnosis of this pathology, the observation of the pregnancy with the help of weekly ultrasounds and the intrauterine interventions can increase the survival chances of the donor fetus from the TRAP sequence.