Modelling futility in the setting of fertility treatment.

When is a fertility treatment futile? This question has great practical importance, given the role futility plays in ethical, legal and clinical discussions. Here, we outline a novel method of determining futility for IVF treatments. Our approach is distinctive for considering the economic value attached to the intended aim of IVF treatments, i.e. the birth of a child, rather than just the effects on prospective parents and the health system in general. We draw on the commonly used metric, quality-adjusted life years (QALYs), to attach a monetary value to new lives created through IVF. We then define futility as treatments in which the chance of achieving a live birth is so low that IVF is no longer a cost-effective intervention given the economic value of new births. This model indicates that IVF treatments in which the chance of a live birth are