What is zygote intrafallopian transfer (ZIFT)?
One of the least often used forms of ART (assisted reproductive technology), zygote intrafallopian transfer (ZIFT) is a combination of IVF and GIFT.
ZIFT is an assisted reproductive procedure similar to in vitro fertilization and embryo transfer with 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 fact that ZIFT transfers a fertilized egg directly into the fallopian tubes versus a mixture of sperm and eggs, is the main difference between ZIFT and GIFT.
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 collected through an aspiration procedure.
- The eggs are fertilized in a laboratory just like in the IVF procedure.
- The fertilized eggs are transferred through a laparoscopic procedure. The catheter is placed deep in the fallopian tube and the fertilized eggs are injected.
- The last 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 is 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.
What are the similarities and differences between ZIFT and in vitro fertilization (IVF)?
ZIFT and IVF both tend to be a favorable treatment for women who have more severe infertility concerns, 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 procedure places the fertilized embryo into the uterus.
The ZIFT procedure differs from IVF in that the transfer of embryos into the tube requires an extra surgical procedure called a laparoscopy.
This is a type of surgery that involves a small incision being made just below your navel into which a tiny tube is inserted. Through this tube, the fertilized eggs will be deposited into your fallopian tubes. Between one and four embryos are usually transferred. The embryos will then be left to travel on their own down through your fallopian tubes and into your uterus.
ZIFT can offer couples more reassurance than GIFT because the process of fertilization can be observed. However, compared to IVF, ZIFT doesn’t offer much insight into the development process of the embryos.
Is ZIFT For You?
Women who have a history of ectopic pregnancies or other tubal problems should avoid using this method. You need to have at least one unblocked and fully functioning fallopian tube for this procedure to have any chance of success. Your partner should be able to provide a decent sperm sample. Men with a low sperm count may still be suitable for this technique so long as their count isn’t too low. Men with abnormally low sperm counts may want to use intracytoplasmic sperm injection with ZIFT.
Pregnancy Success With ZIFT
On average, 36% of women are able to get pregnant using ZIFT, while 29% of women have a live birth. However, because several eggs are transferred back to the woman, 35% of the pregnancies that result from ZIFT are multiples with the majority of them being triplets or more. Additionally, there is an increased risk of ectopic pregnancy with this method.
If you plan to use this form of ART, you can expect to pay between $8,000 and $13,000 per cycle or possibly more depending on which clinic you use. However, because this technology is not very popular, fewer and fewer fertility clinics are actually offering this service. Those that do may charge more for it than they do for IVF and GIFT, both of which have similar pregnancy success rates.
(information from - http://www.americanpregnancy.org/infertility/zift.html and http://www.fertilityfactor.com/infertility_medical_options_zift.html)