1. Oxford Centre for Diabetes, Endocrinology, and Metabolism (T.M.B., J.A.H.W., F.K., M.I.M.), Churchill Hospital, Oxford OX3 7LJ, United Kingdom
2. Department of Radiology (C.A., S.J.G.), John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom
3. Institute of Reproductive and Developmental Biology (S.F.), Imperial College (Hammersmith Campus), London W12 0NN, United Kingdom