Problems of ART-mediated realization of reproductive function in carriers of structural chromosomal abnormalities

Background. Predicting the outcomes of assisted reproductive technology (ART) cycles in couples where one of the spouses is a carrier of chromosome translocations is of importance.

Objective: to determine how the type of chromosomal translocation and carriers gender affect the embryological stage of ART cycles in a couple where one of the spouses is a carrier of a reciprocal or Robertsonian translocation.

Methods. The analyzed data included 137 embryological protocols of ART cycles of 100 couples, in which one of the spouses was a carrier of a reciprocal (31 women and 27 men) or Robertsonian translocation (21 women and 21 men).

Results. The effect of the translocation type and the carrier gender on the efficiency of fertilization and preimplantation development of embryos was analyzed. In the Robertsonian translocation carriers, the frequency of bipronuclear zygotes and the ability of embryos to develop up to day 3 are higher when a carrier is a female (U=490, p=0.024 and U=476, p=0.044, respectively). When a carrier is a man, the frequency of bipronuclear zygotes and the ability of embryos to develop up to day 3 were significantly higher in the case of reciprocal compared to Robertsonian translocation (84.6% versus 75%, U=528, p=0.017 and 59.5% versus 50%, U=512, p=0.034, respectively), which indicates negative selection of embryos before the day 3 specifically in male-carriers of Robertsonian translocation. The ability of embryos to develop up to the day 5 did not differ statistically significantly between the study groups (Mann-Whitney test, p>0.05).

Conclusion. The results of the embryological stage of ART cycles in couples in which one of the spouses is a carrier of a chromosomal translocation are characterized by the lowest values for male-carriers of the Robertsonian translocation.

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