Already at birth, each woman carries all the egg cells she will ever have. They remain dormant at Prophase I. Between puberty and menopause roughly one egg cell per cycle matures to Metaphase II (several eggs mature to Metaphase II in a stimulated cycle). In this phase, the egg has produced a polar body and a haploid set of chromosomes. The egg can now be fertilised. After fusion with the sperm, the egg produces another polar body (2 PB). A polar body contains the same genetic information as the egg. Polar body analysis allows us to examine the egg's genetic material.

Process: We use a laser to open the zona pellucida. The first and second polar bodies are aspired between 16 and 18 hours after fertilisation and sent to the Human Genetics Institute at Graz University. There, using modern CGH methods, the polar bodies are examined for genetic abnormalities, i.e. the amount of genetic material.

About three days after the puncture, we receive the results, which we discuss in detail with the client before transferring the embryo. Transfer can take place, as usual, on the fifth day after puncture, when the embryo is at the blastocyst stage.

ARRAY-CGH:

The Array-CGH is a molecular cytogenetic test that scans the entire genome for abnormalities. This method yields a 100 times better resolution compared to chromosomal analysis.

So far all methods used to test for genetic abnormalities have their limitations. Molecular cytogenetic methods, such as FISH, or molecular genetic methods, such as MPLA, yield higher resolutions, but you have to know or suspect which part of the genome is affected.

Sterignost recommends PBD only in cases when the couple already has a child suffering from a genetic disease, or when the mother suffers a known genetic disease. Abortus Habitualis can be an indicator in some cases.

We do not practice PBD when the mother's high age is the only ground for concern, since a polar body diagnosis will not be useful. According to a random study carried out by the Free University of Brussels (inventor of the ICSI method and the most experienced European clinic for preimplantation diagnostics), there is no higher pregnancy rate associated with women of a higher age through PBD (see the contribution from the Oxford Journal). A consortium of experts convened by ESHRE (European Society of Human Reproduction and Endocrinology) in 2009 came to the same conclusion. One study was even stopped early when it showed that PBD led to a reduced pregnancy rate.

An examination of the embryo is desirable when the man suffers from a genetic condition, but this is banned in Austria. We refer these patients to clinics in Brussels or Bratislava.