Gamete intra-fallopian transfer (GIFT) is a treatment for infertility that is still performed but that is used much less frequently than in vitro fertilisation (IVF). Instead of a couple having their eggs and sperm mixed and fertilised outside the body before having one of the tiny embryos transferred into the woman’s uterus, gamete intra-fallopian transfer simply combines the eggs and sperm and puts this mixture directly into the fallopian tube. Fertilisation, if it occurs, takes place inside the body.
Couples who want to start a family but have been unable to conceive may want to have assisted reproduction but may have cultural or religious reasons why they cannot have in vitro fertilisation (IVF). Gamete intra-fallopian transfer is, for example, the only form of assisted reproduction that the Catholic Church allows.
This is because the conception occurs naturally after gamete intra-fallopian transfer and there is no choice of which embryo is transferred; it is very much up to the natural selection process which egg is fertilised by which sperm, and there are no spare embryos left over.
Like all methods of assisted reproduction, gamete intra-fallopian transfer has its strengths and its weaknesses. GIFT is no use, for example, if you have blocked fallopian tubes as the mixture of gametes cannot pass down to the uterus.
If you have any of the following infertility issues, a cycle of gamete intra-fallopian transfer may help you to conceive and start building your family:
This is more difficult to estimate as the frequency of IVF procedures has increased in recent years, and the frequency of gamete intra-fallopian transfer is still quite low. Overall, around 20–30 % of gamete intra-fallopian transfer cycles result in pregnancy; some efficient IVF techniques such as blastocyst embryo transfer or assisted hatching can increase the success rates of IVF beyond this. As in IVF, actual success depends very much on your individual circumstances, including your age, what is causing your infertility, and the condition of your eggs and sperm before they are mixed and transferred.
GIFT is similar to IVF in that the first step in the process is to stimulate the woman’s ovaries to release several eggs at once. Usually only one egg is produced each month, so this involves taking hormones to encourage several ovarian follicles to develop. Ultrasound scans are used to check on the size of the ovaries, and egg retrieval then takes place around 10–14 days after hormone treatment begins.
Three hours before the eggs are removed, the male partner’s sperm is collected and prepared by washing, ready for the eggs.
Egg retrieval takes about 20 minutes and is done using a thin catheter that is passed through the wall of the vagina and through the abdominal cavity until it reaches the ovaries with its ripe eggs. Ultrasound is used to guide the gynaecologist to be able to aspirate out the eggs.
To avoid the risk of a multiple birth, only two or three eggs are mixed with the sperm; the number of sperm does not matter only in that there should be hundreds of thousands of them. Immediately after mixing the eggs and sperm in a thin tube, the mixture is transferred into the woman’s body. This is done by laparoscopy; a tiny cut is made in the abdomen and then the laparoscope is placed in position so that the eggs and sperm can be injected directly into one of the fallopian tubes.
After a few hours the couple can then return home, but you will need to take drugs to help the lining of your uterus to mature. If one or more of the eggs is fertilised, this happens in the same way as in a normal conception, and implantation of the embryo or embryos can occur 5–7 days later.
As more than one egg is used in the process of gamete intra-fallopian transfer, there is a risk of multiple pregnancy. The latest guidelines from the Human Embryo and Fertilisation Authority (HFEA) in the UK state that only three eggs should be transferred if a woman is younger than 40, and four are allowed if she is over 40. This helps minimise the risk as there is a greater chance of all the eggs being fertilised and implanted the younger the woman concerned. Of course, it may be that you are delighted by the prospect of having twins, or more, so a multiple birth is not necessarily a bad thing.
Other things that are considered complications of gamete intra-fallopian transfer include: