The medical reasons that may cause you to have a zygote intrafallopian transfer (ZIFT) are known as the "indications" of the procedure. ZIFT is performed only in about two to three percent of fertility assistance cases in the United States. To be considered for the procedure, the following indications should apply to your case:
Failed Pregnancy and Fertility Attempts
Before you're usually considered for zygote intrafallopian transfer, you must have tried to become pregnant through other means (unless you're using a surrogate and/or donor). If you were unaware of significant problems in your reproductive systems and have tried unsuccessfully to become pregnant for at least one year, the next step is usually ovarian stimulation. Using oral or injected hormones (which may be injected into your blood stream or through your uterus into your ovaries), your fertility specialist will attempt to increase the number of eggs your ovaries release in order to increase your chances of becoming pregnant naturally.
Your Candidacy for ZIFT
If your other pregnancy attempts have failed, you may now have an indication for zygote intrafallopian transfer. However, your fertility specialist must first make sure that you're a viable candidate for the procedure. In order to be a candidate for ZIFT, the following must apply:
- Your partner's sperm must be able to penetrate an egg (if not, using a donor's sperm may still be a possibility). Significantly low sperm count may also prohibit the procedure, although intracytoplasmic sperm injection can help increase the success rate of harvesting sperm from men with a low sperm count.
- You must have at least one healthy, unblocked fallopian tube. The procedure may be possible with minor tubal damage, but is not possible with severe tubal damage.
- You cannot have a severe structural problem with your uterus. (A common problem that prohibits the procedure is severe intrauterine adhesions.)
- You should not have a history of ectopic pregnancies (pregnancies in which the fetus develops outside of the uterus in a location such as the fallopian tube; they usually result in miscarriages).
Other Indications for the Procedure
If you meet the initial indications and prove a candidate for zygote intrafallopian transfer, there are a number of other indications that may lead you to procedure. ZIFT has about a five percent better rate of success than a similar fertility treatment, gamete intrafallopian transfer (GIFT), because zygotes (fertilized eggs) are implanted instead of gametes (an unfertilized egg and sperm mixture). ZIFT also mimics a more natural way of becoming pregnant than a fertility treatment like in vitro fertilization (IVF), as fertilization naturally takes place in the fallopian tubes, where the zygotes are implanted during ZIFT. However, because ZIFT (unlike IVF) requires you to be put under general anesthesia or local anesthetic, you must not have an allergy to anesthetic.
The reason why zygote intrafallopian transfer is performed in only a small amount of cases is because in vitro fertilization has a higher success rate on average and is a less invasive procedure. You may be a candidate for IVF as well, as it has similar indications but actually also allows more women, such as those with damaged or missing fallopian tubes, to undergo the procedure.