Epidemiologic Reports Surveys
Broekhuijsen, K.; Ravelli, A.C.; Langenveld, J.; van Pampus, M.G.; van den Berg, P.P.; Mol, B.W.; Franssen, M.T.
Department of Obstetrics and Gynecology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
doi: 10.1097/01.aoa.0000504720.75967.f1