Gamete and Zygote Intrafallopian Transfer (GIFT and ZIFT) for Infertility
infertile couples are affected by conditions that
prevent the sperm and egg from traveling through a
fallopian tube, where fertilization and the first
stage of cell division take place. The following are
assisted reproductive technology (ART) procedures that
are rarely used but may improve the chances of conception in the fallopian
tubes. The first step of each of these treatment cycles is
superovulation, the stimulation of multiple egg
production with a series of hormone injections.
Gamete intrafallopian transfer (GIFT) uses multiple eggs
collected from the ovaries, which are placed into a thin flexible tube
(catheter) along with the sperm to be used. The gametes (both eggs and sperm)
are then injected into the fallopian tubes using a surgical procedure called
Although many people still think of infertility as a "woman's problem," in about 40% of infertile couples, the man is the sole cause or a contributing cause of the inability to conceive. One-third of infertility cases can be attributed to male problems, including low sperm count.
So it's crucial that men get tested for fertility as well as women. Yes, it can be embarrassing, but discovering male fertility problems early can mean earlier treatment and a successful pregnancy. Male infertility testing...
Zygote intrafallopian transfer (ZIFT) combines
in vitro fertilization (IVF) and GIFT. Eggs are
stimulated and collected using IVF methods, then mixed with sperm in the
laboratory. Fertilized eggs (zygotes) are then laparoscopically returned to the
fallopian tubes where they will be carried into the uterus. The goal is for the
zygote to implant in the uterus and develop into a fetus.
Pronuclear stage tubal transfer (PROST), similar to ZIFT, uses
in vitro fertilization but transfers the fertilized egg to the fallopian tube
before cell division occurs.
Because of the higher costs and
risks related to laparoscopy, and the lesser amount of diagnostic information
about embryo development compared with IVF, these procedures are rarely
Ovulation and egg retrieval. To prepare for an assisted reproductive procedure using your
own eggs, you must get daily injections and be closely monitored for 2 weeks
before egg retrieval. At home, you or your partner injects you with
follicle-stimulating hormone (FSH) to stimulate your
ovaries to produce multiple eggs (superovulation). After the first week, your
doctor checks your bloodestrogen levels and uses
ultrasound to see whether eggs are maturing in the
follicles. During the second week, your dosage may
change based on blood tests and other test results. If follicles fully develop,
you are given a human chorionic gonadotropin (hCG) injection to stimulate the
follicles to mature. The mature eggs are collected 34 to 35 hours later by
laparoscopy or needle aspiration guided by ultrasound through the abdomen to
Sperm collection. Sperm are
collected by means of masturbation or by taking sperm from the
testicle (when there is a blockage that prevents sperm
from being ejaculated or when there is a problem with sperm development).
For GIFT, the sperm are then placed in a
tube (catheter) with the eggs. The catheter is inserted through a small
abdominal incision and into a fallopian tube. The eggs and sperm are then
injected into the fallopian tube. Usually, two eggs are placed in each
For ZIFT, in vitro fertilization is performed. The
resulting fertilized eggs (zygotes) are injected into the fallopian tubes in
the same way that GIFT is done. The zygotes then travel into the uterus, where
it is hoped that they will implant and develop.
What To Expect After Treatment
Overall, assisted reproductive
technology (ART)-related injections, monitoring, and procedures are emotionally
and physically demanding of the female partner. Superovulation with hormones
requires regular blood tests, daily injections (some of which are quite
painful), and frequent monitoring by your doctor.
You can expect
to return to daily activities after a routine laparoscopic procedure in less
than a week.
Why It Is Done
GIFT may be appropriate when:
A couple has religious objections to
fertilization taking place outside the body.
A couple with
unexplained infertility only has insurance benefits for GIFT.
For GIFT or ZIFT, a woman must have at least one functional
How Well It Works
ZIFT and GIFT are used rarely enough that specific success
rates aren't nationally available. But what is known about assisted
reproductive technology (ART) includes the use of ZIFT and GIFT.
Risks resulting from laparoscopy (which may be
used to collect eggs) include pelvic infection, puncture of internal organs,
and side effects from general anesthesia.
technologies-including GIFT and ZIFT-increase the risk of multiple
multiple pregnancy is high-risk for both the mother
and the fetuses.
ZIFT success versus the risk of multiple pregnancy
In order for a woman over age 35 to maximize her chances of conceiving
with her own eggs and carrying a healthy pregnancy, she must have more embryos
transferred than a younger woman would. This increases her risk of multiple
Because of the risks to the babies of multiple
pregnancy, experts recommend limiting the number of embryos transferred. Based on your age and your situation, your doctor will recommend a certain number of embryos to be transferred.
Women over 40 have a high rate of embryo loss
when using their own eggs. As an alternative, older women can choose to use
more viable donor eggs.
What To Think About
ZIFT and GIFT procedures using
gametes from both partners account for less than 2% of all ART procedures. The
majority of couples in the United States use in vitro fertilization.1
ART birth rates can be misleading. As a woman
ages past her mid-30s, her egg quality and quantity decline, making it
increasingly unlikely that an ART procedure using her own eggs will result in
pregnancy and a healthy baby. Many women over age 40 choose to use donor eggs,
which greatly improves their chances of giving birth to a healthy child.
ZIFT requires two separate procedures. The first procedure is to
collect the eggs from the woman's ovaries. The second procedure is done several
days later when the fertilized egg (zygote) is placed in her fallopian tube.
If GIFT fails, a doctor does not learn anything about the sperm's
ability to fertilize the eggs. With in vitro fertilization, the sperm
fertilizes the egg in the laboratory, where a health professional can tell
whether fertilization has occurred, and can follow embryo development.
ZIFT and GIFT procedures both cost approximately $15,000 to $20,000 per
attempt. In vitro fertilization usually costs less.