1 Midwifery Research and Education Unit, Hannover Medical School, Germany; now: FHM, University of Applied Sciences, Germany. Electronic address: be.schoene@googlemail.com.
2 Midwifery Research and Education Unit, Hannover Medical School, Germany; now: IMC University of Applied Sciences Krems, Austria.
3 Department of Family Practice, University of British Columbia, Vancouver, British Columbia.
4 Midwifery Research and Education Unit, Hannover Medical School, Germany. Electronic address: Gross.Mechthild@mh-hannover.de.