Preimplantation genetic diagnosis (PGD) allows for the avoidance of genetic diseases during in vitro fertilization. This type of diagnosis is recommended for parents who have at least one hereditary disease. The ability to manipulate embryos outside the maternal body has set a goal for doctors to achieve the transfer of only healthy embryos into the uterine cavity, which implies conducting genetic diagnosis.
Experiments in this field in the late eighties allowed for the birth of a healthy child in a family with a high genetic risk of disease. Since then, PGD techniques have been continuously improved, and in 2002, the thousandth child was born after preimplantation diagnosis was performed.
Today, the PGD procedure in Israel is performed using three methods of obtaining embryonic material:
- biopsy of the 1st and 2nd polar bodies;
- blastomere biopsy of a three-day-old embryo;
- trophectoderm biopsy of a 5- or 6-day-old embryo.
The choice of method depends on specific conditions and limitations. If sex selection of the fetus is necessary, the last two methods are usually applied.
There are many indications for conducting PGD. One of them is the increasing number of chromosomal aneuploidies in older women. The preimplantation diagnosis method allows for the selection of chromosomally healthy embryos.
Diagnosis is especially important for patients with monogenic pathologies, as well as for those with balanced chromosomal translocations. By selecting embryos free of genetic anomalies, the birth of children without severe hereditary diseases is achieved.
In Israel, preimplantation diagnosis is performed for:
- reducing the risk of giving birth to children with genetic anomalies;
- improving the effectiveness of IVF;
- identifying embryos that are carriers of severe diseases;
- determining the sex of the embryo to avoid sex-linked diseases.
Conducting PGD procedures is necessary for:
- women over thirty-five years old;
- women who have had more than three miscarriages;
- men with severe spermatogenesis issues.