Does transferring three or more embryos make sense for a well-defined population of infertility patients undergoing IVF/ICSI?

Recently, there has been a marked increase in the use of Single Embryo Transfer (SET) subsequent to In Vitro Fertili-zation (IVF) and Intracytoplasmic Sperm Injection (ICSI), with the aim of reducing the risk of multiple gestations. However, critics have stated that by reducing the number of embryos transferred, a group of women with an a priori reduced chance of pregnancy are at particular greater risk of undertreatment. This group includes women who are of a certain age (≥ 40 years) or have already received a number of - failed - IVF attempts. We wanted to study whether the practice of three or more embryos being transferred would be of added value to these patients and whether the strategy of Heavy Load Transfer (HLT) is likely to boost the pregnancy rates to an acceptable level. We performed both a literature study and a retrospective cohort analysis of 7,850 IVF/ICSI cycles of early cleavage stage embryo transfer. Notwithstanding the limitations associated with this approach, we contend that HLT in the group of patients with poor prognosis should be recommended. This article outlines a suggested protocol within the legal framework relevant to Belgium.