An extra or missing chromosome. Twin to Twin Transfusion Affects identical twins that share one placenta. Blood passes disproportionately from one baby to the other via blood vessels to which both babies are connected. One baby, the recipient twin, gets too much blood which overloads his or her cardiovascular system, resulting in death from heart failure. The remaining baby, the donor twin, does not get enough blood and may die from severe anemia.
Babies share one placenta and one amniotic sac.
Risk is increased for the knotting of umbilical cords, which may result in death. Increases chance of early labor. Umbilical cord slips through the cervix before baby, may occur before or during labor. Occurs in approximately 1 of every 300 births. Cord can become constricted, blocking blood flow to the babies.