Studies have shown that the risk of hypertension and preeclampsia increases by 5% during the artificial cycle of frozen and thawed embryo transfer. In order to save embryos for transplantation later, they are frozen using the cryopreservation method. Embryo freezing is becoming an increasingly common practice because frozen transfers reduce the risk of hyperstimulation. But the study found that the process of cryopreservation of embryos is associated with a higher risk of blood pressure problems in the mother. A harmful effect on vascular pathologies of high and long-term doses of hormone replacement therapy was revealed. Hormone replacement therapy before embryo transfer is used to prepare the uterus for implantation of frozen-thawed embryos. Also important is the protective effect of the corpus luteum, a naturally developing cluster of cells formed in the ovary early in pregnancy that produces progesterone, which supports the lining of the uterus (endometrium) during pregnancy and improves blood flow. Therefore, hormone replacement therapy can interfere with the function of progesterone and lead to a higher risk of pregnancy-related disorders.