What is Zygote Intrafallopian Transfer?
Zygote Intrafallopian Transfer (ZIFT) is an assisted reproductive procedure similar to in vitro fertilization and embryo transfer. Since this surgery involves transferring the fertilized egg directly into the tubes, the procedure is also referred to as tubal embryo transfer or TET.
ZIFT requires healthy fallopian tubes, unlike GIFT, in which fertilization of the already fertilized embryo inside the tube is to be done, involving more success rates, which is an unequivocal sign of fertilization, in contrast to in vitro fertilization and embryo transfer.
Who can receive ZIFT treatment?
ZIFT usually becomes an option for couples who have failed at five or six cycles of ovarian stimulation with intrauterine insemination. Couples who, while having tried conception for at least a year, have been unable to also turn to this course of treatment.
ZIFT is considered an assisted reproductive technique that treats many infertility problems except the following problems:
- Tubal damage
- Blockage of the tubules
- Sperm is unable to enter an egg
- Uterine-related anatomical problem
The ZIFT treatment requires healthy, unobstructed fallopian tubes so that the embryo can be deposited into the uterus after being passed through the inserted tubes. Thus, ZIFT is not practical unless at least one fallopian tube is open and operating normally.
Conversely, the ZIFT procedure is contraindicated in patients with previous ectopic pregnancies or abnormalities of the uterus.
What are the phases involved in ZIFT?
One treatment for zygote intrafallopian transfer takes about four to six weeks. Numerous early stages of ZIFT are remarkably similar to those of IVF.
- Stimulate Ovary: The patient or the female partner in the selected marriage will be given medication to stimulate the ovaries and produce mature eggs. This action prevents the body from releasing the eggs prematurely.
- Development of folliculles: In drug treatment of fertility, the patient has to visit their doctor every two to three days. This is because your doctor may want to measure your developing follicles with the help of ultrasound technology and check your blood hormone level.
- Gathering of the eggs: After the administration of anesthesia to the patient, your doctor will probe the patient’s ovaries with an ultrasound when the eggs are ready for resurrection. During this stage, a tiny needle is inserted through the wall of the vagina and eight to fifteen eggs are aspirated from the patient.
- Incubation: The female’s eggs are then fertilized with her partner’s or a donor’s sperm in a clean laboratory. They are then closely monitored, and after one day, each successfully fertilized egg develops into a zygote a single-celled embryo.
- Surgery: The doctor injects anesthesia into the patient before the zygote develops and performs a laparoscopy. With the help of a small tube called the laparoscope, almost five zygotes are introduced into the fallopian tubes. After this process, the patient needs some rest time to recuperate fully.
- Implantation and the Development of the Baby: Upon successful implantation, the zygote reaches the female patient’s uterus via the fallopian tube. The baby will then develop inside the uterus. The chances of pregnancy increase if more than one zygote is transferred. However, with that comes the added possibility that the patient may experience more than one pregnancy.
What are the main differences between ZIFT and GIFT?
ZIFT and GIFT are alternative modified methods of in vitro fertilization. ZIFT inserts the fertilized eggs within 24 hours, while in GIFT, sperm and eggs are mixed and inserted immediately. Both retrieve an egg from the woman and involve re-implantation; they are different only in their respective timing.
What are the advantages of ZIFT?
Compared to conventional IVF, ZIFT offers several advantages, including no intrauterine manipulation, simulation of natural physiological processes, and laboratory proof of fertilization. Though mixed findings about its effectiveness are available, it is an option for patients who have repeatedly failed to implant embryos during IVF cycles or standard embryo transfers. ZIFT also maximizes the synchronization of the uterine lining and embryo growth.
What are the disadvantages of ZIFT?
ZIFT is less expensive and less risky as compared to the transcervical and uterine embryo transfers. However, it includes surgical and other side effects. It is less preferred to IVF and also transcervical embryo transfer because it increases a risk of multiple pregnancies and ectopic pregnancies.
Why is the ZIFT no longer in use?
It is no longer used because a better pregnancy rate is achieved by intrauterine embryo transfer.
The results obtained with the ZIFT method are not as good as those obtained with utero transfers. It is also an invasive procedure as it consists of laparoscopic surgery and requires sedation of the patient.
How successful is the use of the ZIFT method?
Approximately 40–45% of pregnancies occur using the ZIFT approach, and about 20–25% of GIFT women become pregnant.