Background:
The twin reversed arterial perfusion syndrome (TRAP sequence) is a rare congenital sequence and a serious complication of monochorionic multiple pregnancies. The frequency of this sequence is estimated at 1:35,000 pregnancies and 1% of monochorionic pregnancies. In this sequence, one fetus is described as a “semi-donor” or “twin-pumping” (autosite), and the second as a twin acardiac (acardiac twin). The cause is considered to be arteriovenous anastomoses in the placenta, which lead to blood transfusion between the twins.

Material and methods:
In this article, we report a case of monochorionic monoamniotic pregnancy resulting from natural fertilization, complicated by TRAP sequence.

Results:
The patient gave birth by cesarean section at 34 weeks’ gestation to a neonate weighing 2350 g, length 43 cm, with an Apgar score of 8/10.

Conclusions:
The outcome of a course of maternity care and possible treatment options in the event of TRAP sequence, as reviewed in the literature, are presented in the article.