In the study, nutritional supplementation contained 250kcal, consisting of 6g of lipids, 40g of carbohydrates, 9g of protein, vitamins and minerals, consumed three times per day. Nutritional intervention also significantly prolonged the time between the diagnosis of TTTS and delivery (9.4 ± 3.7 weeks versus 4.6 ± 6.5 weeks; P = 0.014). The earlier nutritional regimen was introduced, the lesser chance of detecting TTTS ( P = 0.001). Although not statistically significant, dietary intervention was also associated with lower Quintero stage, fewer invasive treatments, and lower twin birth weight discordance.Diet supplementation appears to counter maternal metabolic abnormalities in monochorionic twin pregnancies and improve perinatal outcomes in TTTS when combined with the standard therapeutic options. Nutritional therapy appears to be most effective in mitigating cases that are caught in Quintero Stage I, little effect has been observed in those that are beyond Stage I. Epidemiology
Based on recent (2005) US NCHS data, the rate of multiple births is now approximately 3.4% (4,138,349 total births, of which 139,816 were twins or higher-order multiple births). The majority of identical twins share a common (monochorionic) placenta, and of these approximately 15% go on to develop TTTS.
Even with treatment, the condition is associated with premature birth and a risk of cerebral palsy in a surviving fetus. Around 5–15% of identical twin fetuses will go on to develop TTTS. The condition was first described by German obstetrician Friedrich Schatz in 1875. Cause
As a result of sharing a single placenta, the blood supplies of monochorionic twin fetuses can become connected, so that they share blood circulation: although each fetus uses its own portion of the placenta, the connecting blood vessels within the placenta allow blood to pass from one twin to the other. It is thought that most monochorionic placentae have these "shared connections" that cross the placenta, with the net flow volumes being equal between them. This state is sometimes referred to as "flow balance". When the placenta has deep vein–artery connection, this can cause blood flow to become unbalanced.Depending on the number, type and direction of the interconnecting blood vessels (anastomoses), blood can be transferred disproportionately from one twin (the "donor") to the other (the "recipient"), due to a state of "flow imbalance" imparted by new blood vessel growth across the placental "equator", the line that divides each babys proportion of the shared placenta. This state of transfusion causes the donor twin to have decreased blood volume, retarding the donors development and growth, and also decreased urinary output, leading to a lower than normal level of amniotic fluid (becoming oligohydramnios).