Changing the way in which successful IVF treatment is defined offers a tool to improve efficacy while reducing costs and complications of treatment. Crucial to this paradigm shift is the move away from considering outcomes in terms of the single IVF cycle, and towards the started IVF treatment as a whole. We propose the most informative end-point of success in IVF to be the term singleton birth rate per started IVF treatment (or per given time period) in the overall context of patient discomfort, complications and costs. These end-points are important not only for patients, but also for clinicians, health economists and policy makers. Such an approach would encourage the development of patient-friendly and cheaper stimulation protocols with less stress, discomfort and side effects. The combination of mild ovarian stimulation with single embryo transfer may provide the same overall pregnancy rate per total IVF treatment, achieved in the same amount of time for similar direct costs, but with reduced patient stress and discomfort, and the near complete elimination of multiple pregnancies. This would offer major health and indirect cost benefits. If IVF success rates were to be expressed in terms of delivery of a term single baby per IVF treatment (or in a given treatment period), the introduction of single embryo transfer on a large scale would be facilitated.