Distribution of placental glucose transporters in first and third trimester human placenta. This figure shows the distribution of glucose transporters in first and third trimester human placenta as described in Section 3. The localization of GLUT8, 9a and 9b in the first trimester is unknown. No information is available on GLUT10 localization in either first or third trimester. MVM, microvillous membrane; BM, basal membrane; STB, syncytiotrophoblast; CTB, cytotrophoblast; EC, endothelial cell; VS, villous stromal cell.