PubMed2001
Medicine is going from success to success, but with the ever-increasing expectations of the society, the more it achieves, the less it satisfies. This is also true for reproductive medicine. Indeed, advances in basic research and the practical applications of the research that have been performed since the first successful in vitro fertilisation (IVF) in 1978, have given rise to hitherto unimaginable strategies for achieving human reproduction. Couples, that were considered sterile only a few years ago, can now acquire assistance conceiving. Twenty two years after Louise Brown was born, the reproductive medicine methods have spread all over the world and thousands of children have been born as a result of these techniques. ICSI applied to epididymal or testicular sperm in cases of azoospermia permits infertile men to become fathers. Even if the results of reproductive medicine have improved in terms of numbers of pregnancies, it is still striking that it is necessary to use stimulation which sometimes leads to hyperstimulation and multiple pregnancies, that embryo development in vitro is still limited, that implantation only occurs for 15-20% of embryos and this ratio have not changed in the last 20 years. The pregnancy rates currently obtained with IVF are at the most similar to those occurring in vivo. We still need to improve techniques to gain pregnancy rates approaching 50% per embryo. In order to fullfil this task, we need to introduce less aggressive and much simpler ovarian stimulation, routine culture of embryos to the blastocyst stage, pre-implantation genetic diagnosis, cryopreservation and in vitro maturation of oocytes and finally to improve the implantation rates by our ability to understand and control the dialog between blastocyst and receptive endometrium.