Effect of embryo transfer depth on IVF/ICSI outcomes: A randomized clinical trial
Background: Although there has been remarkable advancement in the field of assisted reproductive technology, implantation failure remains a significant issue in most infertile couples receiving these treatments. Embryo transfer is important in assisted reproductive technology and directly affects the implantation rates and pregnancy outcomes.
Objective: To assess the effect of two different distance embryo transfer sites from fundal endometrial surface on the outcomes of in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles.
Materials and Methods: A total of 180 women who were candidate for IVF/ ICSI/ embryo transfer in Yazd Research and Clinical Center for Infertility were equally assigned to two groups based on the distance between the fundal endometrial surface and catheter tip to investigate implantation, chemical and clinical pregnancy (group A: 15 ± 5 mm and group B: 25 ± 5 mm, respectively).
Results: The subjects in the group B showed significantly higher implantation rate, chemical and clinical pregnancy rate compared to the group A (p = 0.03, 0.01, 0.04, respectively). The rate of ongoing pregnancy and miscarriage indicated no significant differences between groups (p = 0.21, 0.27, respectively).
Conclusion: In conclusion, our study showed that the depth of embryo replacement inside the uterine cavity at a distance of 25 ± 5 mm beneath fundal endometrial surface have better effects on the pregnancy outcomes of IVF/ICSI cycles and can be considered as an important factor to improve the success of IVF cycles.
Key words: Embryo transfer, Endometrium, Pregnancy outcomes, IVF, ICSI.
 Eftekhar M, Janati S, Rahsepar M, Aflatoonian A. Effect of oocyte activation with calcium ionophore on ICSI outcomes in teratospermia: A randomized clinical trial. Iran J Reprod Med 2013; 11: 875–882.
 De Neubourg D, Gerris J, Mangelschots K, Van Royen E, Vercruyssen M, Elseviers M. Single top quality embryo transfer as a model for prediction of early pregnancy outcome. Hum Reprod 2004; 19: 1476–1479.
 Strandell A, Bergh C, Lundin K. Selection of patients suitable for one-embryo transfer may reduce the rate of multiple births by half without impairment of overall birth rates. Hum Reprod 2000; 15: 2520–2525.
 Schoolcraft WB, Surrey ES, Gardner DK. Embryo transfer: techniques and variables affecting success. Fertil Steril 2001; 76: 863–870.
 Coroleu B, Carreras O, Veiga A, Martell A, Martinez F, Belil I, et al. Embryo transfer under ultrasound guidance improves pregnancy rates after in-vitro fertilization. Hum Reprod 2000; 15: 616–620.
 Matorras R, Urquijo E, Mendoza R, Corcostegui B, Exposito A, Rodriguez-Escudero FJ. Ultrasound-guided embryo transfer improves pregnancy rates and increases the frequency of easy transfers. Hum Reprod 2002; 17: 1762– 1766.
 Aichberger L, Boldizsar A, Herczeg C, Obermair A, Plockinger B, Strohmer H, et al. [Vaginal ultrasonographic observation of uterine contractions in embryo transfer and its relevance to treatment success]. Geburtshilfe Frauenheilk 1991; 51: 27–30. (in German)
 Baba K, Ishihara O, Hayashi N, Saitoh M, Taya J, Kinoshita K. Where does the embryo implant after embryo transfer in humans? Fertil Steril 2000; 73: 123–125.
 Frankfurter D, Silva CP, Mota F, Trimarchi JB, Keefe DL. The transfer point is a novel measure of embryo placement. Fertil Steril 2003; 79: 1416–1421.
 Frankfurter D, Trimarchi JB, Silva CP, Keefe DL. Middle to lower uterine segment embryo transfer improves implantation and pregnancy rates compared with fundal embryo transfer. Fertil Steril 2004; 81: 1273–1277.
 Krampl E, Zegermacher G, Eichler C, Obruca A, Strohmer H, Feichtinger W. Air in the uterine cavity after embryo transfer. Fertil Steril 1995; 63: 366–370.
 Coroleu B, Barri PN, Carreras O, Martinez F, Parriego M, Hereter L, et al. The influence of the depth of embryo replacement into the uterine cavity on implantation rates after IVF: a controlled, ultrasound-guided study. Hum Reprod 2002; 17: 341–346.
 Franco Jr JG, Martins AM, Baruffi RL, Mauri AL, Petersen CG, Felipe V, et al. Best site for embryo transfer: the upper or lower half of endometrial cavity? Hum Reprod 2004; 19: 1785–1790.
 Pope CS, Cook EK, Arny M, Novak A, Grow DR. Influence of embryo transfer depth on in vitro fertilization and embryo transfer outcomes. Fertil Steril 2004; 81: 51–58.
 van Weering HG, Schats R, McDonnell J, Vink JM, Vermeiden JP, Hompes PG. The impact of the embryo transfer catheter on the pregnancy rate in IVF. Hum Reprod 2002; 17: 666–670.
 Abou-Setta AM. What is the best site for embryo deposition? A systematic review and meta-analysis using direct and adjusted indirect comparisons. Reprod Biomed Online 2007; 14: 611–619.
 Pacchiarotti A, Mohamed MA, Micara G, Tranquilli D, Linari A, Espinola SM, et al. The impact of the depth of embryo replacement on IVF outcome. J Assist Reprod Genet 2007; 24: 189–193.
 Oliveira JB, Martins AM, Baruffi RL, Mauri AL, Petersen CG, Felipe V, et al. Increased implantation and pregnancy rates obtained by placing the tip of the transfer catheter in the central area of the endometrial cavity. Reprod Biomed Online 2004; 9: 435–441.
 Woolcott R, Stanger J. Potentially important variables identified by transvaginal ultrasound-guided embryo transfer. Hum Reprod 1997; 12: 963–966.
 Lesny P, Killick SR, Tetlow RL, Robinson J, Maguiness SD. Embryo transfer–can we learn anything new from the observation of junctional zone contractions? Hum Reprod 1998; 13: 1540–1546.
 Nazari A, Askari HA, Check JH, O’Shaughnessy A. Embryo transfer technique as a cause of ectopic pregnancy in in vitro fertilization. Fertil Steril 1993; 60: 919–921.
 Tiras B, Polat M, Korucuoglu U, Zeyneloglu HB, Yarali H. Impact of embryo replacement depth on in vitro fertilization and embryo transfer outcomes. Fertil Steril 2010; 94: 1341–1345.
 Sallam HN. Embryo transfer: factors involved in optimizing the success. Curr Opin Obstet Gynecol 2005; 17: 289– 298.
 Ivanovski M, Popovska S. The impact of the depth of embryo replacement into the uterine cavity under transabdominal ultrasound guidance on in vitro fertilization and embryo transfer outcome. Maced J Med Sci 2013; 6: 376–382.
 Cavagna M, Contart P, Petersen CG, Mauri AL, Martins AM, Baruffi RL, et al. Implantation sites after embryo transfer into the central area of the uterine cavity. Reprod Biomed Online 2006; 13: 541–546.
 Waterstone J, Curson R, Parsons J. Embryo transfer to low uterine cavity. Lancet 1991; 337: 1413.
 Naaktgeboren N, Dieben S, Heijnsbroek I, Verburg H, Van der Westerlaken L. Embryo transfer, easier said than done. Fertility and Sterility 1998; 70 (Suppl.): S352.
 Salam Mohamed MA. The influence of the depth of embryo transfer into the uterine cavity on implantation rate. Middle East Fertil Soc J 2010; 15: 174–178.
 Tanksale SJ NP, Nadkarni AA, Singh P. Where is the best site for embryo transfer? A study of relation of embryofundal distance with pregnancy rate in ICSI-ET cycle. Int J Reprod Contracept Obstet Gynecol 2016; 5: 2661–2665.
 Meldrum DR, Chetkowski R, Steingold KA, de Ziegler D, Cedars MI, Hamilton M. Evolution of a highly successful in vitro fertilization-embryo transfer program. Fertil Steril 1987; 48: 86–93.
 van de Pas MM, Weima S, Looman CW, Broekmans FJ. The use of fixed distance embryo transfer after IVF/ICSI equalizes the success rates among physicians. Hum Reprod 2003; 18: 774–780.
 Rosenlund B, Sjoblom P, Hillensjo T. Pregnancy outcome related to the site of embryo deposition in the uterus. J Aassist Reprod Genet 1996; 13: 511–513.
 Egbase PE, Al-Sharhan M, Grudzinskas JG. Influence of position and length of uterus on implantation and clinical pregnancy rates in IVF and embryo transfer treatment cycles. Hum Reprod 2000; 15: 1943–1946.
 Yovich JL, Turner SR, Murphy AJ. Embryo transfer technique as a cause of ectopic pregnancies in in vitro fertilization. Fertil Steril 1985; 44: 318–321.