While TTTS has occasionally been detected beyond this timepoint, it is thought that its occurrence beyond week 30 may be due to a placental embolism that upsets the flow balance of the shared connections between the babies. TTTS is potentially lethal to either or both twins, no matter when it is detected. However, when detected past week 25, emergency delivery may be considered to rescue the babies if the TTTS is severe. Other than requiring a monochorionic twin (or higher multiple) pregnancy, the underlying causes of TTTS are not known. It is not known to be hereditary or genetic. Some doctors recommend complete bed-rest for the mother coupled with massive intakes of protein as a therapy to try to counteract the syndrome. Research completed shows these nutritional supplements do work. Diet supplementation was associated with lower overall incidence of TTTS (20/52 versus 8/51, P = 0.02) and with lower prevalence of TTTS at delivery (18/52 versus 6/51, P = 0.012) when compared with no supplementation. 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. The fetal demise of one of the twins during the second trimester of a monochorionic pregnancy can result in serious complications to the surviving fetus. Complications include gangrenous limbs, hands and feet, cerebral palsy and IQ deficits, constriction rings of limbs and digits, reduced digits, skin defects, brain cysts, hydranencephaly, multicystic encephalomalacia, microencephaly, renal agenesis and bowel atresia. There are three hypotheses explaining these complications.