Lucilla Poston is Head of the Division of Reproduction and Endocrinology at King’s College London. Her early work on small arteries in human placenta was pivotal to understanding fetoplacental circulatory control. She was the first to demonstrate directly that pre-eclampsia was associated with profound vascular endothelial dysfunction. The Maternal and Fetal Research Unit which she founded and directs has carried out many large randomised controlled trials in the field of obstetrics, involving a total of more than 10,000 patients. Notable was the trial published in the Lancet showing that antioxidant supplements do not prevent pre-eclampsia which changed perspectives on the disease worldwide.