Preimplantation Genetic Diagnosis (PGD)
Preimplantation genetic diagnosis (PGD) genetic screening is used to identify embryonic abnormalities prior to implantation during in-vitro fertilization (IVF). The PGD process isolates a single cell from an embryo and analyzes it to look for chromosomal abnormalities or inherited genetic diseases. This helps to ensure that healthy embryos are selected for transfer to the uterus, increasing the likelihood of a successful pregnancy.
This genetic screening technology is giving hope to couples who are carriers of high-risk genetic disorders. Detection of these disorders during pregnancy has been possible thanks to genetic screening; however, when offspring do test positive, the parents face the dilemma of whether or not to terminate the pregnancy. Preimplantation genetic diagnosis, also referred to as preimplantation genetic screening, is a revolutionary alternative in which inherited conditions can be detected in embryos before pregnancy is established. Only unaffected embryos are then transferred to the uterus.
The PGD Process
Currently, preimplantation genetic diagnosis is only available for women who undergo in-vitro fertilization (IVF). Eggs are harvested from the mother and fertilized in a lab with the father's sperm. After fertilization, the PGD process can begin. A single cell is removed from the embryo and analyzed to determine if genetic or chromosomal defects are present. If preimplantation genetic diagnosis reveals no potential problems, the embryo is transferred to the uterus. PGD genetic screening is currently only an option for couples whose offspring are at high risk (25-50 percent) for a specific genetic condition.
Genetic Screening before Pregnancy
Prenatal testing, or genetic screening, is an option for couples who wish to improve their chances of carrying a pregnancy to full term. These tests can identify genetic markers in embryos prior to implantation, allowing only the implantation of healthy embryos devoid of debilitating genetic conditions such as Huntington's disease and Down's syndrome, and unaffected by genetic markers that may inhibit implantation in the uterus. Genetic screening does not pose risks for the patient and can provide reassurance and peace of mind during the pregnancy.
Benefits of Genetic Screening
Prenatal genetic screening is meant to increase the likelihood that parents will have a healthy baby. Genetic screening can provide parents with reassurance and peace of mind during pregnancy.
Preimplantation genetic diagnosis substantially improves the chances of a successful pregnancy for women who may have been unable to conceive or carry a pregnancy to full-term in the past. Women who have healthy, PGD-screened embryos implanted in the uterus during in-vitro fertilization are less likely to suffer miscarriage or pass on genetic diseases to their offspring.
PGD can help couples at risk for passing on any of the following genetic disorders:
- Huntington's disease
- Sickle Cell Anemia
- Cystic Fibrosis
- Tay Sachs
- Hemophilia A
- Muscular Dystrophy
- Down's Syndrome
Ethical Issues and Genetic Screening
Genetic screening can eradicate illness in a new - preemptive - way. In doing so, genetic screening has the potential to change society's fundamental attitudes toward:
- Social responsibility
Some people have expressed concern over preimplantation genetic diagnosis being used routinely for genetic screening. Though PGD is a reliable and proven method for identifying genetic abnormalities, ethical issues have been raised about this method of genetic screening, including concerns over the disposal of "unhealthy" embryos.
PGD Success Rates
The success rate for gender selection of embryos is extremely high—nearly 100 percent. There are many gender selection specialists who refuse to perform pre-conception gender selection for couples seeking elective sex selection. However, there are a handful of fertility centers that will treat couples seeking both elective and medical gender selection.
Elective vs. Medical Gender Selection
When it comes to gender selection, there are two basic reasons behind the decision to choose a child of a particular sex. When a couple is trying to conceive and wishes to use sex selection to avoid certain genetic or chromosomal disorders in their baby, the process is called medical gender selection. Infantile Tay-Sachs disease is one example of a fatal genetic disorder, which can be unknowingly passed on through both parents, but can possibly be prevented by prenatal gender selection.
Elective gender selection means that the couple is not choosing the sex of their baby based upon any medical concerns, but simply the desire to have a child of a specific gender. Elective sex selection is pursued for many reasons, including what is referred to as "family balancing," when a couple has several children of one gender, they may desire to have at least one child of the opposite sex.
Regardless of whether a couple is seeking elective or medical gender selection, the methods of sex selection are essentially the same. Learn more about gender selection methods below.
Locate a Fertility Doctor
DocShop provides you with a direct connection to some of the nation's most highly regarded medical professionals. DocShop can help you locate a genetic screening or preimplantation genetic diagnosis specialist in your area. If you would like to know more about the prenatal genetic screening or the PGD process, or you would like to arrange a consultation with a fertility specialist, DocShop will make it easy for you. Find a fertility specialist in your area today.
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