Introduction: In the Dutch maternity care system, the role division between independently practising midwives (who take care of normal pregnancy and childbirth) and obstetricians (who care for pathologic pregnancy and childbirth) has been established in the so-called " List of Obstetric Indications" (LOI). The LOI designates the most appropriate care provider for women with defined medical or obstetric conditions. Methods: This descriptive study analysed the evolution of the concept of " normality" by comparing the development and the contents of the consecutive versions of the LOI from 1958 onwards. The results were related to data from available Dutch national databases concerning maternity care. Results: The number of conditions defined in the successive lists increased from 39 in 1958 to 143 in 2003. In the course of time, the nature and the content of many indications changed, as did the assignment to the most appropriate care provider. The basic assumptions of the Dutch maternity care system remained stable: the conviction that pregnancy and childbirth fundamentally are physiologic processes, the strong position of the independently practising midwife, and the choice between home or hospital birth for low-risk women. Nevertheless, the odds of the obstetrician being involved in the birth process increased from 24.7% in 1964 to 59.4% in 2002, whereas the role of the primary care provider decreased correspondingly. Discussion: Multidisciplinary research is urgently needed to better determine the risk status and the optimal type of care and care provider for each individual woman in her specific situation, taking into account the risk of both under- and over-treatment. Safely keeping women in primary care could be considered one of a midwife's interventions, just as a referral to secondary care may be. The art of midwifery and risk selection is to balance both interventions, in order to end up with the optimal result for mother and child. © 2010 American College of Nurse-Midwives.