Picture of Twin-to-Twin Transfusion
Twin to twin transfusion syndrome (TTTS) occurs in identical twins or multiples when the blood vessels of the babies' shared placenta are connected causing one twin to transfer more blood to the other. At birth, the babies have different skin color because of the blood flow with one usually being abnormally pale and the other appearing red. Over time, their colors will change as normal blood counts are established. TTTS occurs about 15 % of the time among identical twins.
Text Source: Johns Hopkins Medicine
American Pregnancy Association
National Library of Medicine