Implantation Flashcards
Burton et.al., 2001
Process of implantation- interaction between the implanting conceptus and the endometrium.
O’Leary et.al., 2013
Embryo Morphology- what morphology to track.
- Normal vs abnormal fertilization (PN grading)
- Blastomere shape and size
- Optimal/fragmented cleavage and morula stage
Campbell et.al., 2013
Benefits of time lapse technology for embryo morphology interpretations.
Meseuger et.al., 2012
Time lapse technology increased pregnancy rates by 20%.
Munne et.al., 1995
Tried to link increasing maternal age with aneuploidy by taking embryo biopsy from patients undergoing IVF. Found that increasing maternal age is linked to aneuploidy but the problem arises when embryos become polyploid mosaic. But genetic testing can bring two advantages; reduce the risk of trisomy and increases chances of pregnancy.
Wang et.al., 2014
Historically, the aneuploidy screening of embryonic biopsies was carried out used single- cell fluorescent in situ hybridisation (FISH). However, 25-38% of embryos transferred to patients still presented aneuploidy despite the analysis of the 5-12 chromosomes this screening could probe.
Need new technologies that can screen for all sequences of a genre in order to make a pre-implantation genetic diagnosis.
Campbell et.al., 2013 [2]
Morphokinetics- describes the time specific changes that occur during embryonic development that provides dynamic information on a fertilised egg. MARKERS
This study compared the morphokinetics of euploid and aneuploid embryos.
This found that aneuploid embryos had significantly delayed development when compared to their euploid counterparts.
There exists, however, an error detection and repair system which could prolong karyo- and cytokinesis in individual cells with mitotic errors thus leading to delayed blastulation.
Ottolini et.al., 2014
Disagrees with Campbell et al, [2] saying that maternal age instead of aneuploidy is the likely causative factor despite morphokinetic markers.
Campbell was proposing that faster developing blastocysts were suitable embryos and ready for implantation, despite having lower aneuploid risks. Pre-eclampsia risks etc with fast developing embryos as the placental cells will not have developed.
Kroener et.al., 2013
Disagrees with Campbell et al, [2] saying that delayed blastulation is not associated with increased aneuploidy rates.
Suggested that because Campbell did not include maternal age, the rates of aneuploidy between younger and older women had created bias in the findings. Should have been considered as a confounding factor.
Shaw et.al., 2013
Investigate global gene expression profile in three key developmental stages spanning human pre-implantation embryo development.
- Metaphase II oocyte
- 4-cell stage embryo (EGA)
- Blastocyst (before implantation)
Different gene expression in different cells at same stages and different stages.
Boumann et.al., 2007
Quiet embryo hypothesis
Leese et.al., 2016
The Goldilocks Principle
