It has been possible to acquire extensive insight into the relationship between prenatal and perinatal experiences and the course of later development, as well as the possibilities of therapeutic and prophylactic intervention in very different methodological ways. This great diversity of methods, however, makes communication sometimes difficult especially with colleagues in medicine, psychology and psychotherapy who are oriented to academic concepts of science. Since 2007, five different methodological levels (ML) in prenatal psychology have been formulated: 1. The quantitative level 2. The qualitative level 3. The level of empathic insight 4. The level of practical knowledge of professional groups 5. The level of cultural psychological comparison. One-sided restrictions at the methodological level hold dangerous problems and decisively limit the quality of treatment and prevention and the validity of results. Furthermore it is clear that there are no alternatives to integration and balancing of the methodological levels in theory and practice, especially since the unborn baby is not able to choose or to limit himself to one of the levels. The importance for the practical work in the field of obstetrics will be emphasized