Testing embryos on mutations used in artificial insemination reduces the chances of successful completion of pregnancy, Dutch scientists believe.

The essence of the method of preimplantation genetic diagnosis, referred to in the study, is the counting of chromosomes in a single cell extracted from the embryo on the third day after fertilization. In the presence of deviations from the normal number of chromosomes, the embryos under study are rejected. It is believed that this procedure can reduce the risk of chromosomal mutations, which increases with the age of the future mother, as reported by the Internet publication for girls and women from 14 to 35 years Pannochka. Net A study conducted by the staff of the Academic Medical Center of Amsterdam, involved 400 women 35-41 years, half of whom were implanted with genetically tested embryos. Twelve weeks after implantation, only 25% of them remained pregnant. In the control group, where the embryos were not tested, this index was 37%.

According to the researchers, the procedure for harvesting a cell of a three-day embryo for research may not be as safe as previously thought. On the third day of development, a normal human embryo consists of only 9 cells, and taking one of them can significantly reduce the chances of its normal development. In addition, the technique of detecting chromosomal mutations on a single cell does not exclude errors in diagnosis: theoretically, the embryo can be mosaic, that is, it consists of cells with different sets of chromosomes, therefore one can judge its normality with respect to a single cell only with a certain degree of probability.

The lead author of the study, Sebastiaan Mastenbroek (Sebastiaan Mastenbroek) believes that, given the new data, it is necessary with great caution to this high-tech technique. In most cases, says Masterbrook, physicians should be satisfied with the selection of embryos according to their morphological features: their shape and number of cells.

However, a number of experts consider the conclusions of the Dutch colleagues too radical.

So, according to the expert in embryology of Yale University Dagan Wells, the benefits of excluding chromosomal mutations leading to the birth of children with severe developmental disorders outweigh the possible risk of pregnancy failure. In addition, Wells notes that the effectiveness of embryo selection largely depends on the level of laboratories and standards of research methods used, which can vary significantly even in laboratories of one country.

Medicinform. Net.

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