How often does Twin to Twin Transfusion Syndrome Happen?
It is difficult to answer this question with certainty, because formal tracking mechanisms to record TTTS pregnancies are only now being established. Many pregnancies go undiagnosed or unrecorded. It is crucial to have the placenta analyzed to confirm TTTS and to aid in realistic numbers. This in turn helps to further medical research and helps us prove the seriousness and urgency in fighting this condition. From the data that is available, the rate of multiple birth is now 1 in 45 (OBSTET GYNECOL 84:101, 1994), which raises the number of babies affected by twin to twin transfusion syndrome to 6000. Looking at monochorionic identical twins, it is about 15% that will share blood vessels in such a way that the amount and direction of blood flow favors the larger recipient twin, at the expense of the donor twin. It is important for parents to understand that the babies are normal. They only become affected by what is happening in the placenta. Just as the mother has no control in when the
