Features of the fetal sex ratio in progressive and non-viable pregnancies resulting from assisted reproductive technologies

   Background. One of the most important indicators reflecting differences in the viability of an organism and determining the survival of a population is the sex ratio. This indicator is relatively stable for the entire human population and for individual regions. However, when performing ART, there is a certain risk of a change in the sex ratio at birth, which may be due to the peculiarities of technology and a number of other reasons. In this regard, the question
of whether there are differences in the gender ratio in the initial infertility in marriage, depending on the method of conception: spontaneous conception or the use of various ART technologies, is debatable.

   The aim of the study was to determine the sex ratio of the fetus during pregnancy resulting from the use of assisted reproductive technologies (ART) in comparison with natural conception in couples with infertility.

   Objective. To determine the sex ratio of the fetus during pregnancy resulting from the use of assisted reproductive technologies (ART) in comparison with natural conception in couples with infertility.

   Materials and methods. The analysis of the secondary sex ratio in patients with overcome infertility using various ART technologies (IVF and ICSI) — the main group (N=1177) and spontaneous pregnancy — the comparison group (N=376), as well as the results of cytogenetic studies of abortive material of patients with undeveloped pregnancy after various ART technologies and spontaneous pregnancy.

   Results. The conducted studies have shown that the secondary sex ratio in newborns does not have significant differences depending on the method of pregnancy (spontaneous or traditional IVF). However, in induced pregnancy using ICSI, there is a tendency to shift the ratio towards the female sex, which is due to increased death of embryos with a male karyotype in the early stages of pregnancy. Obviously, female embryos conceived with this technology are more viable if they have a normal karyotype.

   Conclusion. The identified trends require further study for a more reliable assessment of differences in the viability of organisms of different sexes in different periods of ontogenesis during induced pregnancy using the ICSI procedure.

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