Cadmium compounds that enter living organisms pose the potential for serious health effects as they exhibit mutagenic, carcinogenic, gonadotoxic, teratogenic, allergenic and embryotoxic effects. It is important to study the mechanisms of their toxic effect on embryonic development and structural and functional formation of organs of living organisms and to search for their bioantogonists. The purpose of the study was to highlight the results of intragastric administration of cadmium chloride (1.0 mg/kg) with isolated administration and in combination with metal citrates (cerium, germanium, zinc, and nanocomposite (iodine + sulfur + selenium citrates)) on the overall course of rat embryogenesis. Materials and methods. For the study, young female Wistar rats weighing 170-200 g were used. They were divided into 6 groups, depending on the test substances, which they received from the 1st to the 19th day of gestation. Results and discussion. The analysis of the results of the experimental study showed the negative effect of cadmium chloride on the analyzed indicators of embryogenesis (preimplantation mortality, postimplantation mortality, total embryonic mortality), indicators of intrauterine survival, morphological (anatomical) malformations, as well as general delay in fetal development), both on the 13th and 20th days of pregnancy relative to the control group. In particular, the indicators of total embryonic mortality significantly increased by 4.2 times (13th day) and 3.7 times (20th day), with significant increase preimplantation mortality by 6.5 times, postimplantation mortality by 3.0 times on the 13th day of embryonic development, and on the 20th day, the preimplantation mortality indicator was by 14.0 times higher (p <0.01), and the postimplantation mortality indicator was insignificantly by 2.5 times higher than the control group. In the groups of the combined effect of cadmium chloride with metal citrates, there was a proven decrease in the indicators of total embryonic mortality (18.18% - 38.10%), preimplantation mortality (21.43% - 53.85%), postimplantation mortality (20.0% - 66.7%), an increase in the number of fetuses per female (12.66% -36.0%). Conclusion. In groups of the combined effect of cadmium chloride with metal citrates, the obtained data indicate a decrease in the accumulation of cadmium under the influence of the studied citrates, which allows them to be considered as potential bioantagonists of cadmium chloride
