- It 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.
Are there other forms of assisted fertilisation?
- Yes, there are various techniques, and new advances are being constantly developed.
- One of the most significant 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.
- Another alternative is Intrauterine insemination (IUI), which involves putting sperm, which have been sorted for viability, directly into the uterus.
- The aim is to maximise the number of healthy sperm reaching the fallopian tubes and fertilising an egg.
- IUI is often combined with ovarian stimulation to increase egg production and improve the rate of success.
Are there any risks?
- Yes. The fertility drugs used to stimulate egg production can produce side effects.
- In rare instances, the ovaries cannot cope with the increased number of eggs, leading to a condition known as ovarian hyper-stimulaion syndrome.
- In mild forms this causes pain and bloating, but more severe cases can lead to blood clots, and kidney and ovary damage.
- Some assisted conception techniques carry an increased risk of ectopic pregnancy, where the fertilised egg implants in the fallopian tubes instead of the uterus.
Are there other problems?
- IVF is only successful in around 23% of cases and success rates vary across the country from clinic to clinic.
- However, success rates have risen sharply in recent years. The chances of success also depend on individual circumstances. For instance, a woman under 35 who is using her own, fresh eggs has nearly a one in three chance of success.
- In contrast, for women over 44 using their own fresh eggs, the success rate is just 0.8%.
- Different procedures also carry different success rates.
- Guidelines from the National Institute for Health and Clinical Excellence (NICE) published in 2004 recommend that suitable couples receive up to three cycles of IVF treatment on the NHS
- However, several studies suggest that provision on the NHS is much more patchy.
- Private treatment can cost many thousands of pounds.
- 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.
- There have been concerns that, to increase the chances of a successful treatment, IVF clinics have been too reliant on using several embryos per treatment cycle.
- This increases the risk of a multiple pregnancy, which is associated with a higher risk of complications, both for mother and baby.
- Measures have been introduced to limit the number of embryos which are implanted during each IVF treatment to minimise this risk.
- Overall rates of multiple birth in the UK fell from 24% of births in 2005 to 22.7% in 2006.
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, which is currently under review.
