The main difference between pre-implantation genetic diagnosis (PGD) and polar body diagnosis (PBD) lies in the time window of the examination. With PGD, embryos obtained through IVF that already consist of 4-8 cells are examined. Due to existing laws concerning the protection of embryos, many countries (e.g. in Germany) allow the use of PGD only to a limited extent. PBD is carried out in the very small window of time between fertilisation of the egg and merging of the two cell nuclei, when the fertilisation process is not yet completed. PBD is thus used for “pre-fertilisation diagnosis” and is also allowed in countries that prohibit PGD.
Another difference lies in the number of anomalies that can be detected by means of the examinations. Whereas with PGD we can now identify approximately 200 different genetic diseases and abnormalities, Polar body diagnostics is limited to the examination of chromosomal maldistribution. The risk of transmission of genetic diseases is thus not completely excluded with this approach.
For whom can polar body diagnosis be helpful?
- Women over 35 years
- Patients with repeated unsuccessful embryo transfer
- Women with a history of repeated miscarriages
This method is particularly suitable for patients with at least six (or preferably more) eggs. The examination can, however, also be useful in the case of a smaller number of eggs, such as for couples who have undergone several unsuccessful treatments.
As a pioneer in the field of fertility treatment, we have taken a crucial step towards finding the euploid embryo: a new method of PBD makes use of “pre-implantation genetic screening” to enable reliable conclusions to be drawn about the overall chromosomal features of fertilised oocytes. Euploid eggs can be identified with certainty; selective transfer of the more developed cells increases the odds of sustaining the pregnancy.
PBD covers only maldistribution of the mother’s chromosomes. These are the cause of over 80% of maldistribution in the embryo. Chromosomal disorders of the sperm cells or any subsequent maldistribution in the embryo go undetected. If necessary, they could be excluded in subsequent prenatal examinations.
In individual cases it may happen that not every polar body can be subjected to an analysis. Thus, the corresponding eggs cannot be definitively assessed. In such a case, our doctors decide together with the patient whether an embryo transfer should be carried out with these eggs or not – this would make the starting situation the same as it would have been without PBD.
- women over 35 years of age
- patients with repeated unsuccessful embryo transfers
- women with a history of repeated miscarriages
The procedure is particularly suitable for patients with at least six (or more) eggs. However, the test can also be helpful with a smaller number of eggs, for example for couples with several unsuccessful treatments.
Molecular Copy Counting (MCC) is a new procedure that can significantly improve the chances of success of artificial insemination (in vitro fertilisation, IVF).
It was developed by the MVZ Kinderwunsch am Welfenhof and SH-Gen Wiesbaden together with the Laboratory of Molecular Biology (LMB) in Cambridge, one of the world’s most renowned institutes in the field of genetics.
Molecular Copy Counting can be used to precisely determine the quality of egg cells retrieved during artificial fertilisation (IVF). The aim is to select the egg cells that are qualitatively suitable for pregnancy.