Obstetrics & Gynecology>>>>>Obstetrical Complications of Pregnancy
Question 5#

During routine ultrasound surveillance of a twin pregnancy, twin A weighs 1200 g and twin B weighs 750 g. Polyhydramnios is noted around twin A, while twin B has oligohydramnios.

Which of the following statements correctly describes this syndrome?

a. The donor twin develops polyhydramnios more often than the recipient twin
b. Gross differences may be observed between donor and recipient placentas
c. The donor twin usually suffers from a hemolytic anemia
d. The donor twin is more likely to develop widespread thromboses
e. The donor twin often develops polycythemia

Correct Answer is B


In the twin-to-twin transfusion syndrome (TTTS), the donor twin is always anemic. This is not due to a hemolytic process, but rather to the direct transfer of blood to the recipient twin, who becomes polycythemic. The recipient may suffer thromboses secondary to hypertransfusion and subsequent hemoconcentration. Although the donor placenta is usually pale and somewhat atrophied, that of the recipient is typically congested and enlarged. Polyhydramnios can develop in either twin, but is more frequent in the recipient twin due to circulatory overload. When polyhydramnios occurs in the donor, it is due to congestive heart failure caused by severe anemia.