Tubal Transfer
Tubal transfer is often referred to as Gamete Intrafallopian Transfer (GIFT), Zygote Intrafallopian Transfer (ZIFT) or Tubal Embryo Transfer (TET). As with in vitro fertilization, the physician prescribes medications designed to stimulate egg development. The difference between in vitro fertilization and standard tubal transfer procedures is that the gamete, or embryo, is transferred to the fallopian tube rather than the uterus.
Gamete Intrafallopian Transfer (GIFT):
GIFT refers to a procedure in which standard medications are used to stimulate egg production. Egg retrieval is then performed with conventional vaginal ultrasound guided aspiration of the follicles. This is followed by a minor surgical procedure known as a laparoscopy in which the eggs are mixed with the sperm and immediately placed into the fallopian tubes. The resultant fertilized egg descends into the uterus for normal fetal development. This procedure requires that the fallopian tubes are normal and has the advantage that both retrieval and transfer can be done at the same time. The disadvantages are that additional surgery is required (laparoscopy) and that fertilization is not verified before transfer.
Zygote Intrafallopian Transfer (ZIFT):
Zygote intrafallopian transfer is very similar to GIFT in that conventional medications are administered to stimulate egg development. Egg retrieval is performed through transvaginal ultrasound aspiration of the follicles. The embryos are then transferred to the embryology lab where they are fertilized through conventional IVF inseminations or ICSI. The embryos are transferred back to the fallopian tube the following day through a laparoscopy. The advantage of ZIFT is that the embryos are in culture outside the body for only one day before they are transferred back to the fallopian tubes. Only fertilized eggs (embryos) are transferred back to the fallopian tube and therefore fertilization is documented; however embryo development cannot be verified due to the early transfer. A disadvantage of ZIFT is the necessity of a second surgical procedure.
Tubal Embryo Transfer (TET):
Tubal Embryo Transfer is referred to as TET and is very similar to ZIFT. The difference is that the embryos are transferred on a later day, which allows the assessment of embryo growth and development. The transfer of the embryos back to the fallopian tubes is again performed through a laparoscopy. This procedure has the advantages of allowing assessment of egg fertilization and embryo development. The disadvantage is the second surgical procedure.