Cover image supplied by R. Upadhyay, C. Fortique, R. Carroll, U. Kaiser and W. Kuohung of the Division of Endocrinology, Diabetes & Hypertension, Brigham & Women’s Hospital, Harvard Medical School, and the Department of Obstetrics & Gynecology, Boston University School of Medicine, MA, USA. Cross-sectional image of a floating chorionic villus from an 11-week gestational age human placenta, immunostained for placental lactogen and hepatocyte growth factor activator inhibitor 1. The image delineates boundaries between the outer layer of syncytiotrophoblast cells, the middle compartment of cytotrophoblast cells and the inner core of stromal cells.

Cover image supplied by R. Upadhyay, C. Fortique, R. Carroll, U. Kaiser and W. Kuohung of the Division of Endocrinology, Diabetes & Hypertension, Brigham & Women’s Hospital, Harvard Medical School, and the Department of Obstetrics & Gynecology, Boston University School of Medicine, MA, USA. Cross-sectional image of a floating chorionic villus from an 11-week gestational age human placenta, immunostained for placental lactogen and hepatocyte growth factor activator inhibitor 1. The image delineates boundaries between the outer layer of syncytiotrophoblast cells, the middle compartment of cytotrophoblast cells and the inner core of stromal cells.

Cover image supplied by R. Upadhyay, C. Fortique, R. Carroll, U. Kaiser and W. Kuohung of the Division of Endocrinology, Diabetes & Hypertension, Brigham & Women’s Hospital, Harvard Medical School, and the Department of Obstetrics & Gynecology, Boston University School of Medicine, MA, USA. Cross-sectional image of a floating chorionic villus from an 11-week gestational age human placenta, immunostained for placental lactogen and hepatocyte growth factor activator inhibitor 1. The image delineates boundaries between the outer layer of syncytiotrophoblast cells, the middle compartment of cytotrophoblast cells and the inner core of stromal cells.

Cover image supplied by R. Upadhyay, C. Fortique, R. Carroll, U. Kaiser and W. Kuohung of the Division of Endocrinology, Diabetes & Hypertension, Brigham & Women’s Hospital, Harvard Medical School, and the Department of Obstetrics & Gynecology, Boston University School of Medicine, MA, USA. Cross-sectional image of a floating chorionic villus from an 11-week gestational age human placenta, immunostained for placental lactogen and hepatocyte growth factor activator inhibitor 1. The image delineates boundaries between the outer layer of syncytiotrophoblast cells, the middle compartment of cytotrophoblast cells and the inner core of stromal cells.