Therefore, we attempted to detect swidden patches and estimate the swidden extent in Myanmar using free available Landsat images on Google Earth Engine in combination with a decision tree-based plot detection method. However, the extent of swidden agriculture in Myanmar is still in question. In Myan-mar, the swidden agriculture has been practicing as an important livelihood strategy of millions of people, mainly by the ethnic groups. When patients consider transferring mosaic embryos, we provide them with access to genetic counselors to help explain their individual risks based on the specific type of abnormality.Swidden agriculture is a common land use found in the mountainous regions, especially in Southeast Asia. Therefore, even given the possible risks, some patients with only mosaic or abnormal embryos might decide these known or unknown risks are acceptable in their pursuit of parenthood and may choose to transfer these mosaic or abnormal embryos. However, some reports indicate that it may be possible for some embryos with abnormal test results to result in live births of apparently healthy children. Physicians typically are unwilling to knowingly transfer embryos with abnormal test results. The concern, of course, is whether transferring these embryos could lead to living children with significant congenital health issues. Therefore, if you have mosaic and abnormal embryos, an important discussion between you and your doctor is whether they are safe to transfer. It is only a tool to help patients and physicians choose which embryos to transfer. Abnormal – greater than 80 percent of the cells are abnormalĭeciding whether to transfer mosaic embryos.High-level mosaic – 40 to 80 percent of the cells are abnormal.Low-level mosaic – 20 to 40 percent of the cells are abnormal.Normal – fewer than 20 percent of the cells in the embryo are abnormal.Geneticists who work in this field have established the following criteria to label embryos tested with PGT-A: Geneticists have a criteria for mosaicism For this reason, mosaicism does not increase with the parents’ ages and occurs equally in all age groups. Frank chromosomal abnormalities, such as Down’s syndrome, are due to abnormal egg or sperm development and are, therefore, present prior to fertilization. A high-level mosaic embryo would have mostly abnormal cells and a lower percentage of normal cells.Īn important point to make is that mosaicism happens after fertilization, that is after the egg and sperm meet. A low-level mosaic embryo would have mostly normal cells and a lower percentage of abnormal cells. This is called mosaicism.Įmbryos that are mosaic can have different proportions of normal and abnormal cells. Indeed, we are finding that some embryos are not one or the other, but can fall on a spectrum between euploid and aneuploid with some having a mix of normal and abnormal cells. Therefore, the ability to test and choose embryos that are euploid allows for the selection of the best embryos for transfer and hastens the time to that positive pregnancy test!īut as PGT testing has advanced over the past few years, it reveals that not all is black and white with human biology. Abnormal, or aneuploid embryos, do not have the correct number.Īneuploid embryos are the main cause for failed implantation in IVF. In scientific language, normal embryos that contain the correct number of chromosomes are called euploid. Up until a few years ago, PGT-A technology could only provide two results – normal or abnormal. PGT-A samples a few cells from the placental layer of the embryo and tests their chromosomal makeup. Genetic testing can also tell you whether any embryos are classified mosaic embryos. Having more genetic information helps the fertility team decide which embryo is best to transfer during an IVF cycle. With the increased use of PGT-A (preimplantation genetic testing for aneuploidy) in IVF protocols, REIs and their patients have more information than ever about the genetic makeup of embryos. As preimplantation genetic testing has advanced over the years, new classifications of embryos have occured, including mosaic embryos
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