Prospective Randomized Trial Comparing Embryo Transfers of Cases with and without Catheter Rotation during Its Withdrawal

Objective: To compare embryo transfer (ET) technique based on catheter rotation during its withdrawal in cases with unexplained infertility in a prospective, randomized trial (NCT03097042). Methods: Two hundred intracytoplasmic sperm injection (ICSI) patients undergoing ET with cleaving or blastocyst-stage fresh embryos were randomized into 2 groups: cases with (n = 100), and without (n = 100) catheter rotation during its withdrawal. Groups were matched for age and some clinical parameters. A soft catheter was used to transfer a single embryo with catheter rotation during its withdrawal in the study group and without rotation in the control. The use of a stiff catheter or tenaculum was not needed in any case. Groups were compared in terms of cycle characteristics and clinical pregnancy rates. Results: Pregnancy rate was significantly higher in the study group (41 vs. 26%, p = 0.04). Clinical pregnancy rate was also significantly higher in the study group (39 vs. 25%, OR 1.9 [1.1–3.5], p = 0.05). On the other hand, the ongoing pregnancy rate was similar between the 2 groups (33 vs. 23%, p = 0.2). Conclusion: Catheter rotation during its withdrawal may be associated with increased pregnancy and clinical pregnancy rates; however, the difference in ongoing pregnancy rates did not reach statistical significance.