University of Newcastle, New South Wales, Australia Roger Smith AM. MB., BS., Hons., FRACP., FRANZCOG Roger is a clinical endocrinologist with an interest in the endocrine regulation of gestational length and the onset of labour. He is best known for his proposal that the timing of human birth is determined by a biological clock in the placenta linked to placental production of CRH. He is Director of the Mothers and Babies Research Centre at the Hunter Medical Research Institute in Newcastle, NSW and Director of the Endocrine Unit at the John Hunter Hospital. Roger has written for Scientific American, Nature and the New England Journal of Medicine and is the author of over 250 published papers.