Mrs X, G2P1L1 at 26weeks of gestation with monochorionic twin pregnancy has done a routine obstetric scan, which showed oligohydramnios is one fetus and polyhydramnios in other. What do you suspect?
Twin-Twin Transfusion Syndrome (TTTS):Blood is transfused from a donor twin to its recipient sibling such that the donor may eventually become anaemic and its growth may be restricted. In contrast, the recipient becomes polycythemic and may develop circulatory overload manifest as hydrops.The donor twin is pale, and its recipient sibling is Plethoric.Diagnosed based on two criteria: (1) presence of a monochorionic diamniotic pregnancy, and (2) hydramnios defined if the largest veical pocket is >8 cm in one twin and oligohydramnios defined if the largest veical pocket is < 2 cm in the other twin.Once identified, TTTS is typically staged by the Quintero staging system:Stage I--discordant amnionic fluid volumes, but urine is still visible sonographically within the bladder of the donor twin.Stage II--criteria of stage I, but urine is not visible within the donor bladder.Stage III--criteria of stage II and abnormal Doppler studies of the umbilical aery, ductus venosus, or umbilical vein.Stage IV--ascites or frank hydrops in either twin.Stage V--demise of either fetus. Management and Prognosis: is related to Quintero stage and gestational age at presentationSeveral therapies are currently used for TTTS, including amnioreduction, laser ablation of vascular anastomoses, selective feticide, and septostomy (intentional creation of a communication in the dividing amniotic membrane).Reference: William's Obstetrics; 25th edition; Chapter 45; Multifetal pregnancy
Normal repo
TTTS
TRAP
Discordant twins
General obstetrics