The Effect of Embryo Transfer Technique on Pregnancy Outcomes in HRT-FET Cycles Using High-Quality Blastocyst Stage Embryos: a Prospective Cohort Study

Only patients who have high-quality blastocyst stage embryos will be included in the study. Since the implantation potential of high-quality embryos is high, possible embryo-induced implantation failure will be minimized. The positions of the air bubble and the catheter in the endometrial cavity in patients with and without pregnancy will be compared.

In patients participating in the study, the transfer catheter will be loaded using a "three drop technique," in which the drop of medium containing the embryo(s) is/are separated from a preceding and a following drop of the medium by an air bubble.

In hormonally prepared frozen embryo cycles, during embryo transfer in each patient, endometrial thickness, uterine cavity dimensions, distance of transfer catheter to the fundus, distance of released air bubble to the fundus, and distance of air bubble to side walls will be systematically measured and recorded under the guidance of transabdominal ultrasonography.

If the position of the embryo in the endometrial cavity is determined during ET in patients who have achieved pregnancy, an ET technique can be defined that predicts the optimum for the physician who will perform the transfer. Therefore, an increase in implantation and pregnancy rates can be achieved.