What is zygote intrafallopian transfer (ZIFT)?
ZIFT is an assisted reproductive procedure similar to in vitro fertilization and embryo transfer, the difference being that the fertilized embryo is transferred into the fallopian tube instead of the uterus. Because the fertilized egg is transferred directly into the tubes, the procedure is also referred to as tubal embryo transfer (TET). This procedure can be more successful than gamete intrafallopian transfer (GIFT) because your physician has a greater chance of insuring that the egg is fertilized. The woman must have healthy tubes for ZIFT to work.
The main difference between ZIFT and GIFT is that ZIFT transfers a fertilized egg directly into the fallopian tubes while GIFT utilizes a mixture of sperm and eggs.
How is ZIFT performed?
ZIFT is an assisted reproductive procedure that involves the following steps:
- A woman’s ovaries are stimulated with medications to increase the probability of producing multiple eggs.
- Eggs are then collected through an aspiration procedure.
- Those eggs are fertilized in a laboratory in a procedure identical to IVF, with the exception of the time frame. During the ZIFT procedure, fertilized eggs are transferred within 24 hours, versus 3-5 days as used in a regular IVF cycle.
- The fertilized eggs are then transferred through a laparoscopic procedure where a catheter is placed deep in the fallopian tube and the fertilized eggs injected.
- The final step is to watch for early pregnancy symptoms. The fertility specialist will probably use a blood test to determine if pregnancy has occurred.
Who should be treated with ZIFT?
ZIFT is an assisted reproductive procedure which may be the selected form of treatment for any infertility problems except the following:
- Tubal blockage
- Significant tubal damage
- An anatomic problem with the uterus, such as severe intrauterine adhesions
- Sperm that are not able to penetrate an egg
ZIFT is commonly chosen by couples who have failed to conceive after at least one year of trying and who have failed five to six cycles of ovarian stimulation with intrauterine insemination (IUI).
What are the similarities and differences between ZIFT and in vitro fertilization (IVF)?
- ZIFT and IVF both tend to be favorable treatments for women who have more severe infertility issues such as damaged fallopian tubes.
- ZIFT and IVF both involve embryo culture.
- ZIFT and IVF both provide the physician with the opportunity to select only the best quality embryos for transfer.
- ZIFT transfers the fertilized embryo into the fallopian tube whereas the IVF and embryo transfer procedures result in the fertilized embryo being placed into the uterus.
- The ZIFT procedure differs from IVF in that the transfer of embryos into the tube requires an extra surgical procedure called laparoscopy.
- Last Updated: 04/2012
Compiled using information from the following sources:
American Society for Reproductive Medicine (ASRM), http://www.asrm.org