Objective: To determine the relative efficacy of different types of embryo transfer (ET) catheters. Design: Systematic review and meta-analysis of prospective randomized, controlled trials comparing at least two different ET catheters. Setting: Infertility centers providing treatment with in vitro fertilization/embryo transfer (IVF-ET). Patient(s): Women undergoing ET. Intervention(s): Embryo transfer with soft or hard catheters. Main Outcome Measure(s): Clinical pregnancy rate. Result(s): A total of seven prospective trials were identified that compared soft (Cook or Wallace) catheters with hard (TDT, Frydman, Tomcat, Rocket) catheters. The meta-analysis demonstrated an increased chance of clinical pregnancy when soft ET catheters were used. The TDT catheter was compared against both soft catheters and other hard catheters, showing decreased chance of clinical pregnancy when the TDT catheter was used. Six more prospective trials were identified comparing the Cook and Wallace soft catheters, and the meta-analysis of these data showed no demonstrable difference in clinical pregnancy rates. Conclusion(s): An increased chance of clinical pregnancy is achieved when soft ET catheters are used. There appears to be little difference between the Cook and Wallace soft catheters. ©2006 by American Society for Reproductive Medicine.
Buckett, W. M. (2006). A review and meta-analysis of prospective trials comparing different catheters used for embryo transfer. Fertility and Sterility, 85(3), 728–734. https://doi.org/10.1016/j.fertnstert.2005.08.031