Effect of the number and depth of embryos transferred and unilateral or bilateral transfer in tubal embryo transfer (TET)

In: Journal of Assisted Reproduction and Genetics · 1992 · vol. 9(6) , pp. 534–538 · doi:10.1007/bf01204250 · PMID:1299386 · W1982162669
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This study evaluated how embryo number, transfer depth, and unilateral/bilateral placement in tubal embryo transfer affect pregnancy rates.

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This paper evaluated how the number of embryos transferred (two to four), the depth of placement within the fallopian tube(s) (compared across >4 cm versus 3–4 cm), and whether transfer was unilateral or bilateral affected pregnancy initiation in 108 consecutive tubal embryo transfer (TET) cycles. Embryos at the two- to four-cell stage were transferred 48 hours after oocyte retrieval by laparoscopy, with a maximum of four embryos per patient. Pregnancy rates were similar across transfers of two, three, or four embryos, and there was no significant difference by embryo deposition depth within the examined range; bilateral transfer showed a numerically higher pregnancy rate, but the difference from unilateral was not significant. The study’s main stated limitation is that its design and small set of categorical comparisons constrain generalization beyond the specific depth and embryo-number ranges tested, and it does not directly address other factors that could influence outcomes, making it less definitive for broader applicability. The paper does not explicitly discuss endometriosis or adenomyosis; it was included in the corpus via a keyword match in the upstream search index.

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Abstract

PurposeOur purpose was to evaluate the possible effects of the number of embryos transferred, the depth of embryos placed within the tube(s), and unilateral or bilateral tubal transfer on pregnancy initiation in tubal embryo transfer (TET).MethodsOne hundred eight consecutive TET cycles were analyzed. Oocyte retrievals were carried out by transvaginal ultrasound-guided aspiration of follicles. Forty-eight hours after oocyte retrieval, the developing embryos at the stage of two to four cells were transferred into the fallopian tube(s) by laparoscopy. A maximum of four embryos was transferred to each patient.ResultsThe pregnancy rates were similar among the cycles in which two, three, or four embryos were transferred. In addition, there was no significant difference in the pregnancy rate whether the embryos were deposited > 4 cm or between 3 and 4 cm into the tube(s). Although the pregnancy rate was greater in cycles of bilateral tubal transfer, the difference from that of unilateral transfers was not significant.ConclusionOur data indicate that when two to four embryos were transferred and the embryos were placed > or = 3 cm within the tube(s), unilateral or bilateral tubal transfer had little influence on the ultimate success of TET.
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Methods

One hundred eight consecutive TET cycles were analyzed. Oocyte retrievals were carried out by transvaginal ultrasound-guided aspiration of follicles. Forty-eight hours after oocyte retrieval, the developing embryos at the stage of two to four cells were transferred into the fallopian tube(s) by laparoscopy. A maximum of four embryos was transferred to each patient.

Results

The pregnancy rates were similar among the cycles in which two, three, or four embryos were transferred. In addition, there was no significant difference in the pregnancy rate whether the embryos were deposited >4 cm or between 3 and 4 cm into the tube(s). Although the pregnancy rate was greater in cycles of bilateral tubal transfer, the difference from that of unilateral transfers was not significant.

Conclusion

Our data indicate that when two to four embryos were transferred and the embryos were placed ⩾3 cm within the tube(s), unilateral or bilateral tubal transfer had little influence on the ultimate success of TET. Similar content being viewed by others

References

Edwards RG, Steptoe PC: Current status of in vitro fertilization and implantation of human embryos. Lancet 1983;2:1265 Yee B, Rosen GF, Chacon RR, Soubra S, Stone SC: Gamete intrafallopian transfer: The effect of the number of eggs used and the depth of gamete placement on pregnancy initiation. Fertil Steril 1989;52:639–644 Haines CJ, O'Shea RT: Unilateral gamete intrafallopian transfer: The preferred method? Fertil Steril 1989;51:518–519 Haines CJ, O'Shea RT: The effect of unilateral versus bilateral tubal cannulation and the number of oocytes transferred on the outcome of gamete intrafallopian transfer. Fertil Steril 1991;55:423–425 Yovich J, Blackledge DG, Richardson PA, Matson PL, Turner SR, Draper R: Pregnancies following pronuclear stage tubal transfer. Fertil Steril 1987;48:851–857 Balmaceda JP, Gestaldi C, Remohi J, Borrero C, Ord T, Asch RH: Tubal embryo transfer as a treatment of infertility due to male factor. Fertil Steril 1988;50:476–479 Yovich JL, Yovich JM, Edirisingh WR: The relative chance of pregnancy following tubal or uterine transfer procedures. Fertil Steril 1988;49:858–864 Palermo G, Devroey P, Camus M, Grauwe ED, Khan I, Wisanto A, Van Steirteghem AC: Zygote intrafallopian transfer as an alternative treatment for male infertility. Hum Reprod 1989;4:412–415 Pool TB, Ellsworth LR, Garza JR, Martin JE, Miller SS, Atiee SH: Zygote intrafallopian transfer as a treatment for nontubal infertility: A 2-year study. Fertil Steril 1990;54:482–488 Yang YS, Hwang JL, Ho HN, Lien YR, Lin HR, Chiu YH, Lee TY: Translaparoscopic tubal embryo transfer: preliminary experience at National Taiwan University Hospital. Asia-Ocean J Obstet Gynecol 1991;17:255–259 Yang YS, Ho HN, Lien YR, Lin HR, Hsieh CY, Lee TY: Treatment of patients with unexplained infertility: Gamete intrafallopian transfer (GIFT) versus tubal embryo transfer (TET) J Formosan Med Assoc 1991;90:547–550 The American Fertility Society: Revised American Fertility Society classifications of endometriosis: 1985. Fertil Steril 1985;43:351–352 World Health Organization: WHO Laboratory Manual for the Examination of Human Semen and Semen-Cervical Mucus Interaction. Cambridge, University Press, 1987 Lee TY, Hsu MC, Yang YS: Antisperm antibodies in infertility.In Recent Advances in the Management of Infertility, C Chen, SL Tan, WC Chang (eds). Singapore, McGraw-Hill, 1989, pp 311–326 Yang YS, Ko TM, Lien YR, Hsu MC, Chang YK, Lee TY: Sequential use of clomiphene citrate and human menopausal gonadotropin for induction of ovulation. J Formosan Med Assoc 1987;86:1049–1054 Yang YS, Ho HN, Lien YR, Hwang JL, Melinda S, Lin HR, Lee TY: The use of a long-acting gonadotropin-releasing hormone analog (D-Trp-6-LHRH) for improvement of ovarian stimulation in assisted conception programs. J Formosan Med Assoc 1991;90:1081–1085 Quinn PC, Kerin JF, Warnes GM: Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid. Fertil Steril 1985;44:493–498 Sterzik K, Dallanbach C, Schneider V, Sasse V, Dallanbach HG: In vitro fertilization: The degree of endometrial insufficiency varies with the type of ovarian stimulation. Fertil Steril 1988;50:457–462 Yovich J: Tubal transfer: PROST and TEST.In Gamete Physiology, RH Asch, JP Balmaceda, I Johnston (eds). Norwell, Serono Symposia, 1990, pp 305–317 Moawad AH, Hafez ESE: The oviduct and egg transfer.In Human Reproduction: Conception and Contraception, ESE Hafez (ed). Hagerstown, Harper & Row, 1978, pp 201–220 Author information Authors and Affiliations Rights and permissions About this article Cite this article Yang, YS., Melinda, S., Ho, HN. et al. Effect of the number and depth of embryos transferred and unilateral or bilateral transfer in tubal embryo transfer (TET). J Assist Reprod Genet 9, 534–538 (1992). https://doi.org/10.1007/BF01204250 Received: Accepted: Issue date: DOI: https://doi.org/10.1007/BF01204250

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