Mild strategies for IVF: from theory to practice

Abstract

Over the last 25 years, ovarian stimulation for IVF treatment has gradually become more complex, time consuming and expensive. Recently, the downsides of ovarian stimulation have attracted increasing attention. Currently, a shift in the focus of IVF is occurring from striving for maximizing instant success 'at all costs' to developing safer and more patient friendly protocols in which the risks of treatment are minimized while optimizing the chance of a singleton live birth. Strategies involving single embryo transfer and milder ovarian stimulation protocols) have been proposed to provide such a patient friendly strategy. An important concern regarding the use of mild treatment strategies remains the reduction in the per cycle chance of pregnancy. The principle aim of this thesis was to identify means of improving the efficacy and therefore the uptake of milder treatment strategies for IVF such as mild ovarian stimulation and SET. In this thesis it was shown that fear regarding the use of mild stimulation for a reduction in ovarian response or an increase of drop-outs (when the number of treatment cycles needed is increased) is unjustified. Indeed, the retrieval of a modest number of oocytes following mild ovarian stimulation was, in contrast to following conventional ovarian stimulation, associated with optimal pregnancy outcomes. Additionally, patients were found to be willing to undergo an increased number of treatment cycles as long as a mild ovarian stimulation protocol was applied. Furthermore, prediction models were developed to reduce the chance of cancellation following mild stimulation and to provide an evidence based method to identify women who may qualify for the transfer of a single versus two embryos. After external validation the first model should be able to reduce the chance of cancellation following mild stimulation to an average level, the second should lead to an increase the overall pregnancy rate per transfer while maintaining a low number of multiple pregnancies. These interventions could increase the efficacy and implementation of mild treatment strategies.