ARIZONA CENTER FOR FERTILITY STUDIES

ZIFT
Diagram of ZIFT
Zygote intra-fallopian tube transfer (ZIFT) is a program involving stimulation of the ovaries with fertility drugs and transvaginal aspiration of oocytes. The oocytes are taken to the laboratory and mixed with pre-washed sperm or injected with sperm (ICSI). The embrylogist will evaluate the oocytes and sperm in 12 to 14 hours.  If fertilization has occurred, the embryos will be transferred back into an open fallopian tube by laparoscopy.  This may be done 24-48 hours after aspiration of the eggs.

At the beginning of each cycle, a screening ultrasound is done to check for ovarian cysts. The ultrasound is done on day 2 or 3 of the menstral cycle.  If no cysts are found, your medication protocol will be reviewed.  You will be given a schedule to follow for your upcoming appointments. 

Serial vaginal ultrasounds will be done while on fertility medications to confirm and measure development of ovarian follicles.  These are usually done on days 7, 9, and 11 of your cycle; but timing will be individualized based on the growth rate of your follicles.  As you reach the end of a stimulation cycle, the timing becomes critical and appointment times may not be flexible.

When an ovarian follicle or follicles have reached maturity based on ultrasound measurements, your blood will be drawn for two tests:

--Estrogen (a mature follicle produces between 100-300+ units)
--LH (rises to signal the ovary to mature and release eggs)

You will then be instructed on the timing for your "trigger" shot of HCG is given. HCG mimics the natural LH surge and signals the ovaries to release the eggs in 38 hours.  Egg retrieval will be scheduled for 36 hours after administration of HCG. The retrieval is done vaginally and usually requires light IV sedation.

After the eggs have been aspirated, they will be transported to the IVF laboratory to be examined and graded by the embryologist.  They will be placed into pitre dishes with the prepared sperm so that fertilization can occur.  If ICSI is considered necessary, each oocyte will be injected with a single sperm and then placed into dishes for observation.

Progesterone injections will be started the morning after surgery. Instructions for the progesterone injections and the hospital and surgical information will be reviewed the day of your blood draw.

Once the eggs have fertilized, you will be scheduled for laparoscopy to transfer the embryos into your fallopian tube.  Only one tube will be used for the transfer.  Laparoscopy is performed under general anesthesia, and will take 45 minutes to one hour.

A quanitative HCG (blood serum pregnancy test) should be scheduled for 14 days after the egg aspiration.

In the event of pregnancy, all medications will continue until you are instructed to stop.  ACFS will follow your progress with vaginal ultrasounds until 10-14 weeks of pregnancy.

Please call with any questions.  It is our goal to make sure you understand and are comfortable with your chosen treatment.