Multiple attempts at embryo transfer: does this affect in-vitro fertilization treatment outcome?

Abstract

In this study, we retrospectively analysed data from 877 patients who had 1204 embryo transfer procedures following in-vitro fertilization (IVF) at Midland Fertility Services, UK, between January 1991 and December 1995 to investigate the factors contributing to failure of embryo transfer at first attempt and the impact of immediate retransfer of retained embryos on the treatment outcome. Embryos were significantly more likely to be retained when the embryo transfer catheter was contaminated with mucus (3.3 versus 17.8%, P = 0.000001) or blood (3.3 versus 12%, P = 0.00001) and when the transfer procedure was difficult compared with when it was easy (20.3 versus 0.8%, P = 0.00001). There was no significant difference in the clinical pregnancy rate between those who had all their embryos transferred at the first attempt (24.7%) and those who required more than one attempt (23.2%). The types of embryo transfer catheter used in the unit did not show any difference in terms of embryo retention. Although we recommend aspiration of cervical mucus in order to reduce the rate of retained embryos, there is no evidence from our study to suggest that pregnancy rate is compromised when embryos are retained, provided they are discovered and immediately retransferred into the uterine cavity. Immediate retransfer is more convenient to the patients and reduces the laboratory workload without compromising the treatment outcome.

Embryo afterloading: A refinement in embryo transfer technique that may increase clinical pregnancy

“…In addition, the embryos will not pass through the initial inner sheath that was placed through the cervix. In theory, this would decrease mucus contamination of the catheter, which has been proposed to adversely affect implantation either by contamination of the cavity or by causing retention or displacement of the embryos (7,25,26). Consistent with this idea, we demonstrated a statistically significant lower number of transfer catheters contaminated with mucus in the afterload group.…”

Embryo Transfer Catheters: Softer is Easier

“…• Presence of blood or mucus in the catheter during post transfer inspection (Goudas et al, 1998;Mains & Van Voorhis, 2010;Moragianni et al, 2010;Nabi et al, 1997;Schoolcraft et al, 2001;Vasiliki et al, 2010;Van Weering et al, 2002).…”

The Role of Ultrasound in the Evaluation of Endometrial Receptivity Following Assisted Reproductive Treatments

“…Compared with the traditional method, abdominal ultrasound-guided embryo transfer has a number of potential benefits (Hearns-Stokes et al, 2000;Leeton et al, 1982;Nabi et al, 1997;Sallam et al, 2002). First, with the guidance of ultrasound, the catheter can be bent to easily pass through the cervical canal and follow the uterine axis, which helps avoid overstimulation and reduction in incidence of difficult transfers, endometrial trauma (Letterie et al, 1999;Woolcott and Stanger, 1997), and bleeding ( Goudas et al, 1998;Nabi et al, 1997;Sallam et al, 2002) that can cause excessive fundo-uterine contractions at the time of embryo transfer has been associated with lower clinical pregnancy rates (Goudas et al, 1998;Sallam et al, 2002).…”

“…First, with the guidance of ultrasound, the catheter can be bent to easily pass through the cervical canal and follow the uterine axis, which helps avoid overstimulation and reduction in incidence of difficult transfers, endometrial trauma (Letterie et al, 1999;Woolcott and Stanger, 1997), and bleeding ( Goudas et al, 1998;Nabi et al, 1997;Sallam et al, 2002) that can cause excessive fundo-uterine contractions at the time of embryo transfer has been associated with lower clinical pregnancy rates (Goudas et al, 1998;Sallam et al, 2002). Second, the entire process of catheterization and release of the embryos can be visualized, making it easier to place the embryos in the correct position within the uterus (Woolcott and Stanger, 1997) and decrease the chance of improper embryo placement Pope et al, 2004;Rosenlund et al, 1996;Shamonki et al, 2005;Woolcott and Stanger, 1997).…”