Student ID: 4175 102
Total word count: 2,805
Since the birth of the first IVF baby in 1978 (Steptoe & Edwards, 1978), the field of assisted reproduction has seen great changes. One of these changes was that it became a multi-million dollar business. Assisted conception has attracted investors all over the world resulting in a huge commercial market. Different assisted conception centres are in continuous search for technologies to improve the results and to deliver healthy babies. This has resulted in a number of innovations. The problem is that these innovations are not proven to be safe, have a clinical benefit or properly validated (Harper, et al., 2012). New assisted reproduction techniques used for human should be considered experimental until scientific evidence is provided regarding its efficacy and safety. Ideally, new technologies should be first tried on suitable animal model then safety and clinical benefit are assessed using sufficiently powered randomised controlled trials (RCTs) (Brown & Harper, 2012). RCTs are the corner stone of evidence based medicine where the technology and outcomes are evaluated in comparison with a control non-treatment group to determine whether the outcome is due to the actual technology or other factors (Barlow, 2003). Although RCTs can’t be applied to some procedures such as PGD and ICSI as it is impossible to have a non-treatment control group, it is essential for other procedures such as procedures that are claimed to increase delivery rate (e.g. PGS and blastocyst transfer). However, development in assisted conception technologies is both money and patient driven where results from clinical applications are used retrospectively to validate the new technique (Harper, et al., 2012). The list of innovations for assisted conception over the last decade is long and it continues to grow with new ones introduced recently. In this essay, two techniques PGS and analysis of embryo metabolism are discussed to demonstrate the role of research to determine effectiveness, safety and cost-effectiveness.
Pre-implantation genetic screening:
Pre-implantation genetic diagnosis (PGD) is genetic testing for pre-implantation embryos, it is usually performed to diagnose patients who are known to be a carrier of monogenetic disorders (Xu, et al., 1999), sex-linked disorders (Handyside, et al., 1990) or chromosomal abnormalities (Munne, et al., 1995). Now, genetic testing is used for screening for numerical chromosomal abnormalities (Munne, et al., 2003). This has led to the development of the term pre-implantation genetic screening (PGS) to differentiate the use of genetic testing between patients with no known genetic disorders from the original diagnostic use for patients with known indication (Ly, et al., 2011). In other words, while pre-implantation genetic screening (PGS) aim to help patients going through IVF cycles in selection of embryo by analysis of embryonic chromosomes, pre-implantation genetic diagnosis (PGD) is used for couples with high risk of transferring genetic or chromosomal disease to their offspring (Munne, 2009). Since the first case of PGS in 1993 where Munne and colleagues used fluorescence in-situ hybridisation (FISH) to detect chromosomal abnormalities for five chromosomes (Munne, et al., 1993), there are evidence that PGS practice in IVF clinics is growing (Goossens, et al., 2009). According to the European Society of Human Reproduction and Embryology (ESHRE) 66% of all the PGD cycles are PGS for aneuploidy screening (Baruch, et al., 2008). The use of PGS is based on the idea of increasing implantation and live birth rates through reducing spontaneous abortion by detecting aneuploidy in embryos for couples with no known genetic disorder. PGS is performed either by polar body or embryo biopsy to analyse chromosomal structure of the embryo or the oocyte by fluorescence in-situ hybridization...