The Timing of Embryo Transfer Catheter Removal: Should It be Delayed or Done Immediately? A Prospective Randomized Trial

Abstract

Background/Aims: Data on the timing of catheter removal technique following embryo transfer (ET) are quite limited. We aimed to compare the reproductive outcomes of intracytoplasmic sperm injection (ICSI)/ET cycles in which the transfer catheter was removed immediately with those in which the catheter was removed after a delay period and hereby to evaluate the impact that the time interval before removal of the catheter following embryo deposit may have on the fertility outcomes. Methods: A prospective randomized study was designed. ICSI/ET patients <40 years were randomly assigned to either of the group from which catheter was withdrawn immediately within the first 5 s (Group A) or after a 30 s delay (Group B) following ET. Results: Groups A and B consisted of 147 and 148 patients, respectively. Patient demographics and stimulation characteristics were comparable between the groups. Pregnancy rate was 32.2% (95 of 295) and clinical pregnancy rate was 28.8% (85 of 295), whereas ongoing pregnancy was 24.4% (72 of 295) and implantation rate was 29.6% (100 of 338). The comparison of reproductive outcomes revealed no significant differences in pregnancy (p = 0.933), clinical pregnancy (p = 0.673), ongoing pregnancy (p = 0.590), multiple pregnancy (p = 0.801), and implantation rates (p = 0.979) between the groups. Conclusion: No significant difference was observed in the reproductive outcomes between the groups; thus, there appears no requirement to delay the withdrawal of the catheter to improve the outcomes in ICSI cycles.

Does rotation during catheter withdrawal in embryo transfer increase pregnancy rates?

“…In a recent study, the ET catheter was kept in the cavity for an additional 30 s after transfer to prevent the embryo from being withdrawn during catheter withdrawal upon completion of the ET process, but this did not show any positive effect on pregnancy rates. 20 Cleaning the cervical mucus, either with a fine brush or with saline and a cotton swab, may result in bleeding of the cervix. In a study evaluating the effect of blood on the catheter tip, it was proposed that blood found outside the transfer catheter after ET was associated with lower rates of embryo implantation and clinical pregnancy following assisted reproductive technology.…”

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

“…In a recently published study, in which patients were randomly assigned catheter withdrawal either immediately (within the first 5 s) or after a 30-s delay following ET, the authors found no significant difference between the reproductive outcomes of the groups [34]. All these interventions represent attempts to overcome the deleterious effect of mucus on embryo placement and implantation.…”

Ultrasound-guided embryo transfer: summary of the evidence and new perspectives. A systematic review and meta-analysis

“…Embryo transfer has hardly changed since its first descriptions (al-Shawaf et al, 1993;Teixeira et al, 2015). Some variables, such as the avoidance of blood during the procedure (Plowden et al, 2016), the type of catheter used (Van Weering et al, 2002), the timing of catheter removal (Devranoglu et al, 2017;Knutzen et al, 1992) and the period of patient rest (Gaikwad et al, 2013) have been reconsidered and modified several times to improve IVF outcomes, encountering only frustrating or contrasting results.…”