Zygote Intra Fallopian Transfer

Zygote Intra Fallopian Transfer (ZIFT)

ZIFT is a procedure that combines both IVF and GIFT techniques and may be used in couples who have a contributing male factor. Experience has shown that couples with male factor infertility have significantly lower pregnancy rates than couples experiencing other infertility problems. With the GIFT procedure there is no way to verify whether or not fertilization takes place whereas with ZIFT fertilization is verified before a woman has to undergo a surgical procedure and general anesthesia.

The first three steps of a ZIFT procedure are identical to the IVF procedure: ovarian stimulation, ultrasound monitoring, and egg retrieval with sperm collection and preparation. The sperm and eggs are then combined, placed in an incubator, and observed. If normal fertilization takes place, a laparoscopy is performed and the fertilized embryos are transferred to the fallopian tubes using a small tube or catheter. These embryos, however, are transferred in a pronuclear phase of development only.

The national pregnancy rate for women undergoing a ZIFT procedure is 26.5% per zygote transfer. (SART, 1998)

Any pregnancy that is successfully achieved with the use of aggressive Assisted Reproductive Technologies, such as IVF-ET, is at risk for multiple gestation (twins, triplets, etc.), miscarriage, ectopic (tubal) pregnancy, preeclampsia, stillbirth, and congenital anomalies (birth defects). The rate of miscarriage in cycles stimulated with super-ovulation drugs is the same whether or not Assisted Reproduction Technologies were used, but slightly higher than in spontaneous pregnancies achieved during a woman’s natural cycle. Ectopic or tubal pregnancies occur at a higher rate than in the general population. This is thought to be due to either chance reflux into the fallopian tube during embryo transfer or compromised fallopian tube status and not caused by the procedure itself. The incidence of stillbirth or congenital anomalies is the same as seen in the general population, but the risk of multiple gestation is REAL. If a pregnancy results in more than triplets, a selective reduction should be considered.