1. Department of Obstetrics and Gynecology (V.T., D.C.), Hôpital Cochin, Maternité Port-Royal, Université Rene Descartes, F-75014 Paris, France
2. Laboratory of Tumor and Developmental Biology (V.T., F.G., C.M., M.-R.P., A.N., F.F., J.-M.F.), University of Liège, C.R.C.E., Belgium
3. Department of Obstetrics and Gynecology (F.G., J.-F.B., J.-P.S., J.-M.F.), Hôpital de la Citadelle, B-4000 Liège, Belgium
4. Department of Human Embryology (J.-P.S.), University of Liège, Liège, Belgium