IVF or in vitro fertilization (IVF) is a process by which egg cells are fertilized by sperm outside the woman’s womb, in vitro. IVF is a major treatment in infertility when other methods of assisted reproductive technology have failed. The process involves hormonally controlling the ovulatory process, removing ova (eggs) from the woman’s ovaries and letting sperm fertilize them in a fluid medium. The fertilized egg (zygote) is then transferred to the patient’s uterus with the intent to establish a successful pregnancy.
IVF was developed in the 1970s. The first British test tube baby was Louise Brown, who was born in 1978.Some 30,000 test tube babies have been born in the UK since then.
There are several different techniques, but the main process involves the women taking fertility drugs to help her produce more eggs.The eggs are then harvested and fertilised in the laboratory.
The woman is given hormone drugs to prepare her womb to receive the fertilised eggs. The fertilised eggs are placed inside the womb and a normal pregnancy follows.
The term in vitro, from the Latin root meaning in glass, is used, because early biological experiments involving cultivation of tissues outside the living organism from which they came, were carried out in glass containers such as beakers, test tubes, or petri dishes. Today, the term in vitro is used to refer to any biological procedure that is performed outside the organism it would normally be occurring in, to distinguish it from an in vivo procedure, where the tissue remains insided the living organism within which it is normally found. A colloquial term for babies conceived as the result of IVF, test tube babies, refers to the tube-shaped containers of glass or plastic resin, called test tubes, that are commonly used in chemistry labs and biology labs. However in vitro fertilization is usually performed in the shallower containers called petri dishes. (Petri-dishes may also be made of plastic resins.) However, the IVF method of Autologous Endometrial Coculture is actually performed on organic material, but is yet called in vitro.
Around 6,000 babies a year are born in the UK to otherwise infertile couples as a result of in vitro fertilisation.
But the techniques used often arouse huge controversy and some say the process can falsely raise would-be parents’ hopes since it only has a success rate of around 15%.
There have also been cases of fertilised eggs being mixed up in the laboratory and the wrong embryo being transferred to the woman, leading to fears about how the process is carried out.
New techniques coming on stream:
One of the biggest and most controversial advances in IVF in recent years has been the introduction of a technique called ICSI – intra-cytoplasmic sperm injection.
This works by injecting a single sperm directly into an egg.
Some people fear the technique could increase the risk of genetic defects that make the donor infertile being passed on to babies.
ICSI was introduced during the 1990s, but new advances are helping men with a very low sperm count to benefit from it.
These include operations to search for sperm which can be retrieved and injected into an egg.
Another advance being developed at St George’s Hospital in London involves a 3D ultrasound device which helps to spot fertility problems before IVF begins.
For example, it can test whether there are any blockages in a woman’s fallopian tubes that could harm her chances of having a healthy pregnancy.
Other doctors at the hospital are pioneering a technique that could mean an end to hormone treatments and the painful retrieval of eggs from infertile women.
The technique involves collecting thousands of immature eggs from the ovary and developing them in the laboratory.
It works by removing a bit of the skin of the ovary which masks the place where immature eggs develop.
It takes five months to grow there properly and lots of nourishment.
The eggs can be frozen so that they can be used whenever the woman wants.
Again, the technique is controversial because it means a woman could store the eggs and use them at any age.
It is likely to be available in the next 10 years, say doctors at the hospital.
Dr Ian Findlay is also developing a test that can check for 10 genetic abnormalities in one go before a fertilised egg is placed in the womb. He said: “This could lead to a dramatic reduction in miscarriages as the vast majority of miscarriages are due to abnormalities.”
The politics of IVF
IVF is only successful in 15% of cases and a recent report from the College of Health shows that success rates vary widely across the country.
Only 18% of IVF treatment is funded by the NHS and waiting times can differ greatly.
It can cost up to £2,000 per cycle for a couple to go private.
Most couples have three cycles at an average cost of £3,420.
One way of getting free treatment is for women to donate their eggs to other infertile couples.
Opponents of IVF argue that it falsely raises would-be parents’ hopes that they will be able to have a baby when the chances are not that high.
They also argue that it can be a traumatic experience to go through repeated IVF attempts, only to find that the woman does not get pregnant.
Another possible drawback is the fact that IVF treatment increases the chance of having multiple births which the couple may not have planned for.
One to two per cent of pregnant women give birth to more than one child, but with fertility treatment the odds are raised to 25%.
Most of the babies born are twins, but bigger births are on the rise.
Many doctors are worried that they are being put under increasing pressure to use more of the fertility drugs to produce more eggs and so increase the chance of the woman getting pregnant.
Some believe fertility drugs could cause ovarian cancer.
Liz Tiberis, author of ‘No Time to Die’, believes her ovarian cancer was the result of nine attempts at IVF.
But fertility doctors say the link has not been proven.
The Cancer Research Campaign is investigating.
Who regulates the IVF process?
In the UK, the Human Fertilisation and Embryology Authority regulates and licenses fertility clinics under the 1990 Human Fertilisation and Embryology Act.
One area of controversy involves the processes clinics have for ensuring mix-ups do not occur over embryos.
This follows a US case where one woman wrongly received the fertilised egg of another.
Fertility experts say procedures in the UK are very tight and there is unlikely to be the same mix-up here.
But the Medical Protection Society recently reported the case of an expert who transferred three embryos from one woman into another by mistake.
However, he realised his error in time.
Calls have been made for procedures for matching eggs with mothers to be tightened, for example, by stipulating that doctors have to do a DNA test before implantation goes ahead rather than relying on written records.
BBC NEWS:31 March , 1999