Preparation of endometrium for frozen embryo transfer cycles

Abstract

Aim. Aim of the study was to the effectiveness of various endometrial preparation protocols in IVF frozen embryo transfer cycles. Materials and methods. The study included 288 women, which were stratified into two groups depending on the onset of pregnancy: group 1 pregnancy + (n=92), group 2 pregnancy - (n=196). Then endometrium preparation features were evaluated. Results. The pregnancy rate after frozen-thawed embryo transfer was a bit higher in the natural menstrual cycle (41.2%) compared to the hormonal replacement therapy (30.0%); p=0.083. There were no significant differences in the use of various estrogen and progestogen drugs, the average estrogen dose, progestogen administration and the endometrium thickness. In the natural cycle, the odds ratio of pregnancy with the duration menstrual cycle from 28 to 30 days was 4.25 (95% CI 1.15; 17.23). Conclusion. Thus, the pregnancy rate is slightly higher in natural cycle frozen-thawed embryo transfer. However, the duration of the menstrual cycle (from 28 to 30 days) has a key effect on the effectiveness of the IVF program in this case.

Keywords

• assisted reproductive technologies
• embryos
• pregnancy
• embryo freezing
• embryo thawing
• embryo transfer
• cryo-thawed
• frozen-thawed
• natural cycle
• hormone-stimulated cycle
• hormone replacement therapy